Moldex 6420 Rockets Review — NRR 27 Cloth-Cord Reusable Earplug, 50 pairs
WC Safety Editorial Verdict: 4.3/5
WC Safety Editorial Verdict — 4.3 / 5. The Moldex 6420 Rockets is the variant to specify when a plastic cord causes problems: its braided cloth cord stays soft against sweat-soaked or sun-exposed skin and resists the kinking that frustrates outdoor and warm-environment crews, while the NRR 27 triple-flange TPE body delivers roughly 10 dB(A) of real-world OSHA-derated protection — adequate up to a 100 dB(A) TWA. As a reusable earplug it is washable and glove-friendly, though metal-detection facilities must step up to the 6415 and very high noise still demands dual protection; see ear plugs vs ear muffs. We score editorially against the wider hearing protection field; no manufacturer payment or samples were accepted.
Moldex 6420 Rockets Cloth Cord Reusable Earplug Review — NRR 27 for Outdoor and Warm-Environment Hearing Conservation
The difference between a plastic cord and a cloth cord on a reusable earplug might seem cosmetic. It is not. In warm manufacturing environments, outdoor construction sites, and agricultural settings where workers perspire continuously, a plastic monofilament cord can become slick with sweat, abrasive against sun-exposed skin, and prone to kinking and tangling when it thermally expands. The braided cloth cord on the Moldex 6420 Rockets addresses each of these contact points: it is softer against skin, absorbs minimal surface moisture without degrading, and maintains its flexibility across a wider temperature range than equivalent-diameter plastic cords.
Everything else about the 6420 is identical to the rest of the Rockets family — NRR 27 triple-flange TPE body, NIOSH approval under 29 CFR 11.57, push-in insertion compatible with gloves, and washable construction for weeks to months of reusable service. This review is for safety professionals deciding between the cloth-cord 6420 and other Rockets variants, or between the 6420 and competing corded reusable earplugs from other brands.
Editorial Verdict — 4.3 / 5
NRR 27 corded triple-flange TPE earplug with braided cloth cord. Best choice for warm-climate outdoor work or any setting where a plastic cord causes skin irritation or tangling problems. Effective real-world protection: 10 dB(A) per OSHA 50% derating.
Technical Specifications
| Specification | Detail |
|---|---|
| Model Number | Moldex 6420 |
| NRR | 27 dB |
| OSHA-derated protection | 10 dB(A) |
| Body material | Thermoplastic elastomer (TPE) |
| Flange design | Triple-flange, push-in insertion |
| Cord type | Braided cloth cord |
| Reusable | Yes — wash with soap and water |
| Service life | Weeks to months with proper cleaning |
| Quantity per pack | 50 pairs |
| NIOSH approval | 29 CFR 11.57 |
| Country of manufacture | USA (Covina, California) |
The Cloth Cord Advantage — When It Matters Most
Three distinct scenarios favor the cloth cord of the 6420 over the plastic cord of the standard 6405:
1. Warm and outdoor environments. Construction workers, landscaping crews, agricultural equipment operators, and outdoor maintenance personnel work in direct sun at ambient temperatures well above indoor factory norms. Plastic monofilament cords stiffen in cold and become more pliable in heat, but more importantly, they can feel abrasive against the back of a sunburned neck or sweat-soaked collar. The cloth cord's braided textile surface is consistently soft regardless of temperature and absorbs superficial sweat without retaining it (the cord can be rinsed and dried with the earplug bodies).
2. Tangling-prone environments. Workers who regularly don and doff hearing protection — such as those who alternate between loud machine operation and verbal communication tasks — frequently experience plastic cords kinking or tangling in their work clothing, tool harnesses, or personal protective equipment. Cloth cords, with their fibrous surface and greater flexibility, are significantly less prone to kinking and tend to drape naturally rather than coiling into tight loops.
3. Workers with plastic cord sensitivity. A minority of workers report contact dermatitis or localized irritation from extended daily contact with plastic monofilament cords. For these individuals, a cloth cord eliminates the irritant without requiring a complete change to a different earplug body or style.
Rockets Triple-Flange Body — Construction and Performance
The TPE triple-flange body of the 6420 is mechanically identical to all other Rockets variants. Three progressively sized flanges create a graduated seal: the innermost flange seals at canal entry, the mid flange provides the primary acoustic barrier, and the outer flange acts as a secondary seal and physical stop preventing over-insertion. This design is stable across a range of ear canal geometries — it does not rely on a precise canal diameter fit the way some banded or canal cap designs do.
The push-in insertion technique requires no rolling, no compression, and no waiting for foam re-expansion. Workers with gloves on can insert the 6420 as effectively as workers with bare hands. This is particularly relevant in outdoor construction and agricultural settings, where heavy leather gloves, rubber irrigation gloves, or thick work gloves are standard throughout the shift. Explore our safety gloves collection for compatible hand protection options.
Protection Analysis — NRR 27 in Outdoor Environments
Outdoor work environments present different noise exposure profiles than indoor manufacturing. Construction equipment noise is often impulsive or intermittent — jackhammers, concrete saws, and heavy equipment operate at 95–110 dB(A) at operator positions but may cycle on and off. The Rockets' 10 dB(A) OSHA-derated attenuation protects workers in time-weighted average exposures up to 100 dB(A). For intermittent exposures above 100 dB(A) TWA, dual protection (earplugs plus earmuffs) is necessary.
OSHA's construction noise standard (29 CFR 1926.52) uses the same action level and PEL thresholds as the general industry standard (29 CFR 1910.95): 85 dB(A) action level and 90 dB(A) PEL as 8-hour TWA. The 6420 satisfies both standards when TWA is at or below 100 dB(A). For a comprehensive look at hearing protection selection, read our in-ear hearing protection guide.
| Workplace TWA | Estimated Exposure with 6420 | Compliance Status |
|---|---|---|
| 85 dB(A) | 75 dB(A) | Below action level |
| 90 dB(A) | 80 dB(A) | Below PEL |
| 95 dB(A) | 85 dB(A) | Below PEL |
| 100 dB(A) | 90 dB(A) | At PEL — adequate |
| 105 dB(A) | 95 dB(A) | Above PEL — add earmuffs |
Cleaning the Cloth Cord
The cloth cord requires slightly different cleaning consideration than the TPE body. The braided textile can trap particulate contamination between fibers, particularly in dusty outdoor environments. For thorough cleaning:
- Rinse the entire assembly under warm running water, working the cord between fingers to dislodge particulate.
- Apply mild liquid soap and work a lather into the cord as well as the earplug flanges.
- Rinse thoroughly — soap residue in the cloth cord can be an irritant if it contacts the neck.
- Squeeze the cord gently between a clean cloth to remove excess water, then air-dry the complete assembly. Do not wring or twist the cord aggressively as this can fray the braid over time.
- Allow to dry completely before storing. Storing a damp cloth cord in a sealed container can promote mildew; air circulation is important.
Rockets Family Comparison — All Six Variants
- 6400 Uncorded — no cord; lowest cost per pair; workers who keep earplugs in all shift
- 6405 Standard Corded — plastic cord; general manufacturing with loss prevention
- 6415 Metal-Detectable Corded — metal-detectable compound; food/pharma
- 6420 Cloth Cord (this review) — braided cloth cord; outdoor and warm-climate environments
- 6480 Camo Uncorded — camouflage body; range and outdoor aesthetics
- 6485 Camo Corded — camo body with plastic cord; range with loss prevention
Who Should Choose the Moldex 6420
Choose the 6420 when your workers operate outdoors, in high-temperature indoor environments (foundries, bakeries, laundries), or in any setting where workers have complained about plastic cord discomfort. If your workforce is entirely indoor manufacturing with no temperature or cord-comfort complaints, the 6405 standard corded may be a more economical choice. If your facility requires metal-detectability, the 6420's standard TPE cord disqualifies it — specify the 6415 metal-detectable instead.
Browse our complete earplugs collection and hearing protection collection for the full range of options available to industrial safety programs.
Frequently Asked Questions — Moldex 6420 Rockets Cloth Cord
Q: Why choose a cloth cord earplug over a plastic cord earplug?
A: Cloth cords are softer against skin, less prone to kinking and tangling, and maintain flexibility in both warm and cool temperatures better than plastic monofilament. For outdoor workers and those in warm environments, this reduces irritation and improves compliance with cord-based hearing protection programs.
Q: Does the cloth cord affect the NRR of the Moldex 6420?
A: No. The NRR of 27 dB is a property of the earplug body geometry and fit — not the cord. The cloth cord attachment point does not alter the acoustic seal provided by the triple-flange TPE body.
Q: Is the Moldex 6420 NIOSH approved?
A: Yes. The 6420 is NIOSH approved under 29 CFR 11.57 at NRR 27, making it compliant for use in OSHA hearing conservation programs under 29 CFR 1910.95 and 29 CFR 1926.52.
Q: Can I wash the cloth cord?
A: Yes. Rinse the cord with warm water and mild soap, work the lather into the braided fibers, rinse thoroughly, and air-dry. Avoid wringing or twisting the cord aggressively to preserve the braid integrity. Allow the cord to dry fully before storing in a closed container.
Q: Is the Moldex 6420 metal-detectable?
A: No. The 6420 uses standard TPE and a standard cloth cord, neither of which contains metal-detectable compounds. For food processing or pharmaceutical applications requiring metal-detectability, specify the Moldex 6415 metal-detectable corded instead.
Q: How does the 6420 cloth cord differ from the 6405 plastic cord in practice?
A: The cloth cord is softer against skin, drapes more naturally, and resists kinking. In cool environments the difference is minimal. In warm or outdoor environments where the cord contacts perspiring skin all day, most workers report a clear preference for the cloth cord's texture.
Q: Are the Moldex 6420 earplugs one size fits all?
A: The 6420 is a one-size-fits-most adult design. Workers with very small or large canals may find better fit with the Jetz family, which uses extra-soft flanges and a foam-tipped stem. See our Jetz 6455 corded review for comparison.
Q: Can I use the Moldex 6420 with gloves on?
A: Yes. The push-in triple-flange design requires only a gentle push to insert — no rolling or compression. Workers wearing nitrile, latex, rubber, or light leather gloves can insert the 6420 correctly without difficulty.
Q: How many pairs per box for the Moldex 6420?
A: The 6420 is sold in a 50-pair bulk dispenser box, suitable for placement at facility entry points or tool crib stations where workers pick up their assigned pairs at the start of each shift.
Q: What is the OSHA derated protection of the Moldex 6420?
A: (27−7)÷2 = 10 dB(A) of effective noise reduction. This protects workers in environments up to 100 dB(A) TWA. For TWA above 100 dB(A), supplement with earmuffs from our hearing protection collection.
Q: How long does the cloth cord last?
A: With daily washing and careful drying, the cloth cord maintains integrity for the service life of the earplug bodies. Replace the pair when the cord shows fraying, significant fiber separation, or when the earplug flanges show signs of cracking or hardening.
Q: Where is the Moldex 6420 manufactured?
A: Moldex manufactures the 6420 in Covina, California, USA. The domestic manufacturing supports consistent quality and is relevant for facilities with Buy American or domestic-content procurement requirements.
Q: Is the 6420 appropriate for construction work?
A: Yes. The 6420 is well-suited for construction because it handles glove-on insertion, outdoor temperatures, and the push-in technique that is more reliable for intermittent use than roll-down foam. OSHA's construction noise standard (29 CFR 1926.52) is satisfied for TWA up to 100 dB(A).
Q: Can I use the 6420 for shooting range hearing protection?
A: The 6420 provides NRR 27 protection, which is adequate for some range scenarios, but impulse noise from firearms often benefits from higher-NRR options or electronic hearing protection. For range-specific guidance, see our best in-ear hearing protection for shooting guide.
Q: Where can I buy the Moldex 6420 cloth cord earplugs?
A: Purchase directly from WC Safety or find them on Amazon Check Price on Amazon →. WC Safety stocks the complete Moldex Rockets lineup for bulk industrial orders.
Related Resources
- Shop All Earplugs
- Shop All Hearing Protection
- Moldex 6405 Rockets Standard Corded Review
- Moldex 6415 Rockets Metal-Detectable Review
- Moldex 6480 Rockets Camo Uncorded Review
- Moldex 6450 Jetz Uncorded Review
- Best In-Ear Hearing Protection Guide
- Understanding NIOSH Approval Standards
Disclosures & editorial standards
WC Safety participates in the Amazon Services LLC Associates Program. Outbound Amazon links are affiliate links. We accept no manufacturer payment, sponsorship, or product samples. This content is not medical, legal, or regulatory advice. Safety equipment selection is governed by applicable OSHA standards and your facility's safety program.
WC Safety participates in the Amazon Services LLC Associates Program. Outbound Amazon links are affiliate links. We accept no manufacturer payment, sponsorship, or product samples. This content is not medical, legal, or regulatory advice. Safety equipment selection is governed by applicable OSHA standards and your facility's safety program.
Pros & Cons
Pros
- Braided cloth cord stays soft and tangle-resistant against sweat-soaked or sun-exposed skin, where plastic monofilament cords irritate and kink
- Push-in triple-flange TPE body inserts cleanly with gloves on — no roll-down, no foam re-expansion wait
- NRR 27 with a washable, reusable body that lasts weeks to months, lowering cost-per-wear versus single-use foam
- Identical acoustic seal to the rest of the Rockets family, so the cloth cord adds comfort without sacrificing rated attenuation
- Made in Covina, California — relevant for Buy American or domestic-content procurement
- Sold in a 50-pair dispenser box that suits entry-point or tool-crib distribution
Cons
- Not metal-detectable — disqualified for food, beverage, and pharmaceutical lines that require detectable PPE (specify the 6415 instead)
- NRR 27 derates to roughly 10 dB(A), so TWA above 100 dB(A) requires earmuffs over the plugs for dual protection
- Cloth cord traps particulate between fibers and needs more careful rinse-and-dry than a wipe-clean plastic cord
- Higher per-pair cost than the standard 6405 plastic-cord variant, which is wasted spend for purely indoor crews with no cord complaints
- One-size-fits-most flange body may seal poorly for very small or very large ear canals
Who It's For
Buy it if:
- Outdoor construction, landscaping, and agricultural crews working in direct sun and continuous perspiration
- Warm indoor operations — foundries, bakeries, laundries — where plastic cords feel abrasive against the neck all shift
- Workers who report contact irritation or dermatitis from plastic monofilament cords
- Crews that frequently don and doff hearing protection and battle cord kinking in harnesses and clothing
- Safety managers standardizing on a washable, glove-friendly reusable earplug for a 100 dB(A)-or-below TWA program
Look elsewhere if:
- Food, beverage, or pharmaceutical facilities that mandate metal-detectable PPE
- Purely indoor manufacturing crews with no temperature or cord-comfort complaints, who can save money on the plastic-cord 6405
- Workers in TWA above 100 dB(A) who need dual protection or a higher-NRR solution
- Users needing maximum NRR for sustained very-high-noise exposure better served by NRR 33 foam
Related Resources
- foam ear plugs
- hearing protection
- nrr 33 ear plugs
- reusable earplugs
- disposable ear plugs
- what is nrr noise reduction rating explained
- best foam ear plugs
- highest nrr ear plugs
- ear plugs vs ear muffs
- how to insert foam earplugs
- how to calculate the nrr you need
- moldex 6604 sparkplugs
- moldex 6654 sparkplugs corded
- moldex 6615 sparkplugs metal detectable
- moldex 6684 sparkplugs jar
- moldex 6800 pura fit
- moldex 6900 pura fit corded
- moldex 6600 softies
- moldex 6650 softies corded
Frequently Asked Questions
Is the Moldex 6420 worth the extra cost over the standard 6405 plastic-cord version?
It is worth it whenever the cord touches skin all day in heat. The cloth cord's value shows up in compliance: outdoor and warm-environment workers who find the plastic 6405 cord abrasive or tangly tend to leave the plugs out, defeating the program. If your crew is entirely indoor with no cord complaints, the cheaper 6405 is the smarter spend.
How does NRR 27 on the 6420 translate to real-world protection on the job?
NRR is a laboratory value under ANSI S3.19; real-world attenuation is always lower. OSHA applies a 50% safety factor — (27 minus 7) divided by 2 equals about 10 dB(A) of usable reduction. NIOSH's foam-style derating is roughly 25%, but the 6420 is a pre-molded flange plug, so the OSHA estimate is the conservative planning figure. See our explainer on what NRR means.
Is NRR 27 enough, or should I buy the highest-NRR earplug available?
More NRR is not automatically better. NRR 27 covers TWA up to about 100 dB(A) after derating, which fits most construction and manufacturing noise. Over-protecting can isolate a worker from backup alarms and speech. Use our guide to calculate the NRR you need before defaulting to the highest-NRR ear plugs.
How does the 6420 compare to the Moldex Pura-Fit foam earplugs?
Different tools. The 6420 is a reusable, washable triple-flange plug for repeated daily insertion; the foam Moldex 6800 Pura-Fit is a single-use roll-down at a higher NRR (33) and lower cost per pair. Choose the 6420 for reusability and glove-on insertion, the Pura-Fit for maximum attenuation or where roll-down foam is preferred. The corded Moldex 6900 Pura-Fit corded mirrors the 6420's loss-prevention benefit in foam.
Reusable flanged plug or disposable foam — which is right for my program?
Flanged reusables like the 6420 lower cost-per-wear and insert cleanly with gloves, but require cleaning discipline and worker buy-in. Disposable foam from our disposable ear plugs range is hygienic and cheap per use but generates waste and depends on correct roll-down technique. Many programs stock both and let the task dictate the choice.
How does the 6420 compare to the Moldex Sparkplugs?
Sparkplugs use a soft single-flange foam-tipped design that suits workers who want a softer feel than the 6420's firmer triple flange. Compare the uncorded Moldex 6604 Sparkplugs or corded Moldex 6654 Sparkplugs corded if your team finds the Rockets body too firm; the 6420 wins on the cloth cord and a more positive over-insertion stop.
Does the cloth cord change how I should clean and maintain these versus a plastic-cord plug?
Yes. The braided textile traps dust between fibers, so it needs a deliberate rinse and lather rather than a quick wipe, and it must air-dry fully before storage to prevent mildew. Budget a little more cleaning time than a plastic cord, but the trade is worth it for outdoor crews.
How long will a pair of 6420 plugs realistically last in service?
With daily washing and careful drying, expect weeks to months per pair. Retire a pair when the cloth cord frays or separates, or when the TPE flanges harden, crack, or stop sealing. The 50-pair box is sized for ongoing replacement across a crew, not a single year's supply for one worker.
Will the 6420 work for warm or high-temperature indoor environments, not just outdoors?
Yes — foundries, bakeries, commercial laundries, and other hot indoor settings are prime use cases. Anywhere a worker perspires continuously and a plastic cord turns slick or abrasive against the neck, the cloth cord pays off in comfort and compliance just as it does outdoors.
Can the 6420 be used as part of dual hearing protection in very loud work?
Yes. For TWA above 100 dB(A), wear the 6420 under earmuffs for combined attenuation. Combined protection is not simple addition of the two NRRs — the field rule of thumb adds roughly 5 dB to the higher-rated device. Our ear plugs vs ear muffs guide explains layering correctly.
Is the 6420 a good fit for shooting or range hearing protection?
It provides solid passive NRR 27 for some range scenarios, but firearm impulse noise often favors higher-NRR plugs or electronic muffs that let you hear range commands between shots. For a reusable plug at the range the 6420 is serviceable; for serious or frequent shooting, weigh dedicated options first.
How does the firm triple-flange Rockets body feel compared with softer reusable plugs?
The Rockets body is firmer and relies on a positive push-in seat, which many workers prefer for a definite seal and a clear over-insertion stop. Workers who want a plusher feel may prefer the Softies line — see the Moldex 6600 Softies — but those trade some of the Rockets' insertion positivity.
Are these comfortable enough for a full 8-to-12-hour shift?
The triple-flange TPE is designed for all-shift wear, and the cloth cord removes the main long-shift irritant — cord drag against a sweaty neck. Comfort still depends on canal fit; one-size-fits-most works for the majority, but very small or large canals may seal better with a different body style.
Which 6420 variant or pack size should a facility order for shared distribution?
The 6420 ships in a 50-pair dispenser box ideal for entry points or tool-crib stations where workers grab an assigned pair each shift. For loss prevention the corded 6420 is already the right pick; uncorded variants suit workers who keep plugs in continuously rather than letting them hang.
How do I choose between the 6420 and the metal-detectable 6415 for my plant?
Let the contamination-control requirement decide. If any production line mandates metal-detectable PPE — food, beverage, or pharma — you must specify the 6415, because the 6420's standard cloth cord and TPE are not detectable. Everywhere else, the 6420's cloth-cord comfort makes it the better outdoor and warm-environment choice.
Why trust WC Safety
Industrial PPE specialists. We do not accept manufacturer payment for placement.
Industrial PPE specialists. We do not accept manufacturer payment for placement.
Reviewed by
Steven Eaton, WC Safety Editorial — guidance reflects current OSHA, NIOSH and ANSI practice.
Steven Eaton, WC Safety Editorial — guidance reflects current OSHA, NIOSH and ANSI practice.
Our standards
Ratings combine published specs, hands-on familiarity, and verified customer data where available; we do not fabricate lab tests.
Ratings combine published specs, hands-on familiarity, and verified customer data where available; we do not fabricate lab tests.
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