Is the Honeywell 4178CL Fibre-Metal Face Shield Window the right replacement window for your Fibre-Metal crown system?

Short answer: If you already run a Fibre-Metal crown protector and your clear window is scratched or hazed, the Honeywell 4178CL is the correct propionate replacement — it is preformed to the exact crown curve and runs a thicker 0.060" lens than a typical 0.040" window. It is a replacement window, not a complete shield or headgear, so confirm you own a compatible Fibre-Metal crown before buying; if you need the whole assembly instead, look at a Fibre-Metal F300 headgear or an F5500 hard-hat crown. New to face shields entirely? Start with how to choose a face shield.

Honeywell 4178CL Fibre-Metal Face Shield Window Review (2026)

The Honeywell 4178CL is a clear replacement window in Honeywell's Fibre-Metal line — just the lens, with no crown or suspension in the box. Per the listing it is injection-molded propionate, preformed at the factory to the exact curve of Fibre-Metal crown protectors so it seals against dust, dirt, and debris, and it carries a 0.060" thickness versus the ordinary 0.040" window. A face shield is always secondary protection worn over primary eyewear under OSHA 29 CFR 1910.133, so this window rides on a Fibre-Metal crown and still expects safety glasses or goggles underneath — see safety glasses vs face shields for why both layers matter. Because compatibility is system-specific, treat this strictly as a Fibre-Metal part: it is the clear sibling of the 4178DGN dark-green window and the 4178IRUV3 shade-3 IR/UV window, and it does NOT cross to Jackson, MSA, or 3M frames. If you want clear impact-and-splash coverage on a Fibre-Metal F300 crown, this is the lens that belongs on it; browse the full face shields collection if you are still mapping the system.

Editorial verdict — 4.2/5
For anyone already invested in a Fibre-Metal crown, the 4178CL is the cheap, correct way to refresh optics without buying a new assembly — the only real cost is making sure your headgear is genuinely Fibre-Metal before you order.VIEW ON WC SAFETY →CHECK PRICE ON AMAZON →

As an Amazon Associate, WC Safety earns from qualifying purchases. Prices and availability are accurate as of the date shown and are subject to change. Full affiliate disclosure.

Who it is for

• Maintenance and general-manufacturing crews who already run a Fibre-Metal F300 crown and need a fresh clear window
• Hard-hat-mounted workers on an F5500 high-performance crown refreshing scratched optics
• Chemical handlers and lab techs wanting a propionate splash window — pair with safety goggles underneath
• Safety managers standardizing a face shield program on Fibre-Metal and stocking spare clear lenses
• Buyers who need a shade window instead and should jump to the 4178IRUV3 IR/UV shade 3.0 or 4178DGN dark-green sibling
• Anyone unsure whether they even own a Fibre-Metal crown — read how to choose a face shield first

What the Honeywell Fibre-Metal 4178CL does well

Exact-curve preformed fit

The 4178CL is preformed at the factory to the precise curve of Fibre-Metal crown protectors, so it snaps in true and seals against dust, dirt, and debris instead of bowing or gapping the way a flat-cut window can. That fit is the whole reason to buy the matched part rather than a generic lens — see how to choose a face shield.

Thicker 0.060" lens

At 0.060" the window runs noticeably thicker than the ordinary 0.040" lens, which the listing frames as an extra margin of protection. The added rigidity also helps it hold its curve and resist flex-cracking over a longer service life on a Fibre-Metal crown.

Propionate splash resistance

Propionate is the material Fibre-Metal calls superior for window duty, and it holds up well against chemical splash and surface scratching for handling and lab work. Worn over goggles it completes the two-layer setup described in safety glasses vs face shields.

Clear, true-color optics

The clear window keeps color accurate for inspection, fine assembly, and reading labels — important when you are not dealing with radiant heat. For grinding-heavy, impact-first jobs, a polycarbonate complete shield like the Honeywell Uvex Bionic is the better tool.

Cheap re-lens path

Swapping a window is dramatically cheaper than replacing a whole headgear, so a stock of 4178CL lenses keeps a Fibre-Metal program running for years. Compare against buying complete units in the face shields collection.

Where the Honeywell Fibre-Metal 4178CL falls short

No headgear in the box

This is the window only — there is no crown, suspension, or chin guard. Without a compatible Fibre-Metal crown it does nothing, so first-time buyers should price a complete shield from the face shields collection instead.

Fibre-Metal only

The preformed curve that makes it fit Fibre-Metal also locks it out of every other brand. It will not seat on a Jackson 370, an MSA V-Gard frame, or a 3M H8A crown — match the window to your exact system, never cross brands.

Clear, not shaded — and propionate, not polycarbonate

There is no IR/UV shade here, so it is wrong for welding or torch work; choose the 4178IRUV3 shade-3 window for that. And propionate trails polycarbonate in high-velocity impact testing under ANSI Z87.1, so impact-first grinders may prefer a polycarbonate shield.

Honeywell Fibre-Metal 4178CL vs the competition

Compare prices on Amazon →Honeywell Fibre-Metal 4178CL on Amazon[Fibre-Metal 4178DGN](

When to step up from the Honeywell Fibre-Metal 4178CL

If you do not already own a Fibre-Metal crown, stepping up to a complete assembly makes more sense than buying a bare window: a Fibre-Metal F300 headgear gives you the channel-grip crown and suspension the 4178CL needs, while the F5500 hard-hat crown suits cap-mounted use. For impact-first grinding where polycarbonate beats propionate, a complete Honeywell Uvex Bionic shield is the bigger upgrade. And if your hazard is welding or torch cutting, skip clear entirely and move to the 4178IRUV3 shade-3 window or a dedicated shielded unit from the welding-grinding-cutting guide.

Category context

Face shields split into three buyable parts, and getting the category right prevents a wasted order: complete shields (window plus crown and suspension), replacement windows like this 4178CL (lens only), and headgear or crowns (the mount, no lens). The 4178CL is firmly in the middle bucket. Material drives hazard fit — polycarbonate leads in high-velocity impact, propionate and PETG resist chemical splash and crazing, steel mesh handles heat and brush work, and IR/UV shade numbers handle welding and torch radiant heat; this clear propionate window targets splash and general manufacturing, not impact-first grinding or welding. Mount style matters just as much: the 4178CL is a Fibre-Metal crown-protector preform, distinct from a Jackson speed-dial window or a Sellstrom DP4 replacement. Whatever you choose, remember a shield is secondary protection over primary eyewear per ANSI Z87.1 and what Z87+ means, and lean on the best face shields guide when mapping hazard to part.

Total cost of ownership

As a replacement window, the 4178CL is the consumable in a Fibre-Metal program — the crown is the durable asset and the lens is what you cycle. Replace the window when it scratches, hazes, crazes, or takes a splash-etch that distorts vision, which for an active shop can mean every few weeks to a few months depending on grit and chemical exposure; the thicker 0.060" propionate here tends to stretch that interval versus a thin 0.040" lens. Stocking a small shelf of clear 4178CL windows keeps a Fibre-Metal F300 or F5500 crown in service for years at a fraction of new-assembly cost, which is the core economic case for buying the matched part rather than tossing whole shields. Budget shade and tinted siblings (4178DGN, 4178IRUV3) into the same rotation if your crews switch hazards, and see the face shields collection for complete-unit pricing comparisons.

Final verdict

Buy the Honeywell 4178CL if you already own a Fibre-Metal crown and need a clear, true-color propionate window for general manufacturing, maintenance, or chemical-splash work — it is the correct preformed part and the thicker 0.060" lens is a genuine plus. Skip it if you do not have Fibre-Metal headgear (start with an F300 crown or a complete unit from the face shields collection), if your hazard is welding (go 4178IRUV3 shade 3.0 or see the welding/grinding/cutting guide), or if you run a different brand's headgear, in which case match a Jackson or MSA V-Gard window to your own system. Either way, keep safety glasses or goggles underneath — the shield is the second layer, per safety glasses vs face shields.

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Honeywell Fibre-Metal 4178CL FAQ

What headgear does the Honeywell 4178CL window fit?

It is preformed to the exact curve of Fibre-Metal crown protectors, so it fits the Fibre-Metal crown system — for example a Fibre-Metal F300 headgear or F5500 hard-hat crown. Confirm your crown is genuinely Fibre-Metal before ordering; if you are unsure, how to choose a face shield walks through identifying the system.

Is the 4178CL a complete face shield?

No. It is a replacement window only — there is no crown, suspension, or chin guard in the box. If you need the whole assembly, look at a complete unit in the face shields collection instead of this lens.

Will the 4178CL fit a Jackson, MSA, or 3M frame?

No. The preformed curve is specific to Fibre-Metal crowns and will not seat correctly on a Jackson Safety, MSA V-Gard, or 3M H8A frame. Always match the window to your own headgear brand — compatibility is system-specific.

What is the window made of?

The 4178CL is injection-molded propionate, which Fibre-Metal describes as superior for window duty thanks to its chemical-splash and scratch resistance. Propionate is well suited to handling and lab work, though polycarbonate rates higher for high-velocity impact under ANSI Z87.1.

How thick is the 4178CL lens?

It is a 0.060" window, which the listing frames as an extra margin of protection versus an ordinary 0.040" lens. The added thickness also helps it hold its preformed curve and resist flex over a longer service life on a Fibre-Metal crown.

Can I use the 4178CL for welding or torch cutting?

No — it is a clear window with no IR/UV shade, so it offers no protection against welding or torch radiant heat. For that work choose the shaded sibling, the 4178IRUV3 IR/UV shade 3.0, or see the welding/grinding/cutting guide.

Do I still need safety glasses with this shield?

Yes. A face shield is secondary protection worn over primary eyewear under OSHA 29 CFR 1910.133, so you still wear safety glasses or goggles underneath. Safety glasses vs face shields explains why both layers are required.

What is the difference between the 4178CL and the 4178DGN?

Both are Fibre-Metal propionate windows with the same preformed crown fit; the 4178CL is clear for true-color general work, while the 4178DGN is dark-green tinted for glare and brightness control. Pick by lighting, not by fit — both seat on the same crown.

When should I replace the window?

Replace it when it scratches, hazes, crazes, or takes a splash-etch that distorts vision. In a busy shop that can be every few weeks to a few months; the thicker 0.060" propionate here tends to stretch the interval, and re-lensing is far cheaper than buying a new shield from the face shields collection.

Is the 4178CL ANSI Z87.1 compliant?

Run as part of a complete Fibre-Metal shield, the system is listed to ANSI Z87.1 and OSHA 1910.133 for eye and face protection. The window alone is one component of that rated assembly — read ANSI Z87.1 explained and what Z87+ means for how the marks work.

Is propionate or polycarbonate better for my job?

Propionate, like this 4178CL, resists chemical splash and surface scratching and suits handling and lab tasks. Polycarbonate rates higher for high-velocity impact, so for grinding-first work a polycarbonate complete shield such as the Honeywell Uvex Bionic may protect better.

Does the 4178CL come anti-fog coated?

The listing describes it as a hard-coated optical-grade propionate window preformed for fit; it does not advertise an anti-fog layer. If fogging is a problem in your environment, plan on an anti-fog wipe or compare complete shields that list anti-fog coatings in the best face shields guide.

How does the 4178CL compare to the Honeywell 11390064 visor?

Both are Honeywell propionate replacement windows, but they fit different systems: the 4178CL is preformed for Fibre-Metal crowns, while the 11390064 Protector visor fits Honeywell Protector-shield frames and is noted to meet high-velocity impact requirements. Match the part to your actual headgear, not just the brand name.

Can I mount the 4178CL on a hard hat?

Indirectly — the window itself has no mount, but it seats on Fibre-Metal crowns, and a crown like the F5500 supports cap or hard-hat use. You need the matching Fibre-Metal crown and any required hard-hat adapter; the window does not attach to a hard hat on its own.

Is the 4178CL good for chemical splash?

Yes — propionate handles chemical splash well, and the listing groups it with chemical-handling and lab use, with the preformed seal helping keep splash and debris out. Wear it over chemical-splash goggles for full protection, since the shield is the secondary layer.

How many windows come in a 4178CL order?

Pack count and price can vary on an affiliate listing, so confirm the quantity before checkout rather than assuming a multi-pack. For program planning, stock spares so a Fibre-Metal crown is never down waiting on a lens.

What if I don't already own Fibre-Metal headgear?

Then this bare window is the wrong starting point — buy a complete shield or a crown first. An F300 headgear gives you the crown and suspension the 4178CL needs, or pick a ready-to-wear unit from the face shields collection and add spare windows later.