DiamondFinish Clear is a flexible clear coat for metal. It is a water clear, high gloss, single component film that stays permanently flexible, takes impact without cracking, and holds up to sunlight without yellowing. The video below shows its durability and flexibility.
Updated October 2026 by the KBS Coatings technical team.
Watch the DiamondFinish Clear Durability Video
This 40 second video shows the durability and flexibility of DiamondFinish Clear, a tough clear coat that goes on direct to metal or over other coatings.
What Makes DiamondFinish Clear a Flexible Clear Coat?
DiamondFinish Clear stays permanently flexible as it cures, so the film moves with the metal instead of cracking off it. It survives 160 inch-pounds of direct and indirect impact and reaches 7H pencil hardness at seven days, which is a hard film that still takes a hit.
That combination matters on metal that flexes, vibrates or sees temperature swings. A coating that is hard but brittle chips and cracks. DiamondFinish Clear is built to do neither, and it needs no hardener or activator to get there.
Stuck or unsure? Search the KBS Support Desk for instant answers
How Durable Is DiamondFinish Clear Outdoors?
DiamondFinish Clear is UV stable. It holds 1000 hours of QUV 313B accelerated weathering without yellowing or chalking. On engine parts it performs without yellowing up to 325 degrees F, including cylinder heads, engine blocks, brake components and inlet manifolds.
One limit to know: the clear itself will not yellow, but it does not block UV from reaching what is underneath it. A color coat under the clear still needs to be UV stable on its own.
DiamondFinish Clear at a Glance
| Finish | High gloss. The liquid is high gloss only. |
|---|---|
| Type | 1K moisture cured, no hardener or activator |
| Applied to | Bare metal (direct to metal) or over other coatings |
| Application temperature | 50 to 82 degrees F |
| Cure | Average 1 to 2 hours depending on humidity; hard in about 4 days |
| Hardness | 7H pencil hardness at seven days |
| Impact resistance | 160 inch-pounds |
| Heat | No yellowing up to 325 degrees F on engine parts |
| Coverage | 400 sq ft per gallon at 2 mils |
How Do You Apply DiamondFinish Clear?
Apply DiamondFinish Clear between 50 and 82 degrees F, direct to clean metal or over other coatings, and follow the DiamondFinish Clear directions for mixing, thinning and coats. For prep by metal type, use the DiamondFinish Clear direct to metal guide. For a complete starting point, the Clear Coat 1K Quart Kit includes DiamondFinish Clear, KBS Klean and KBS #1 Thinner, and covers up to 100 square feet with single coat coverage.
Do not use UV or bake lights to speed the cure. They slow it down. More application and troubleshooting answers are in the DiamondFinish Clear FAQs.
Frequently Asked Questions About Clear Coat on Metal
What clear coat is best for metal?
The best clear coat for metal bonds to the metal, stays flexible as the metal expands and contracts, and holds up to sunlight without yellowing. DiamondFinish Clear is a 1K clear coat built around those three traits: it goes on direct to metal or over other coatings, stays permanently flexible, and is UV stable.
What is the best clear coat sealant for metal?
Look for a clear coat that cures to a hard, flexible, water clear film rather than a soft rubber layer. DiamondFinish Clear cures to 7H pencil hardness at seven days and survives 160 inch-pounds of impact, so it seals bare or coated metal without cracking or peeling. It is a moisture-cured single component coating, so no hardener is needed.
What is the best heat-resistant clear coat for metal?
DiamondFinish Clear performs on cylinder heads, engine blocks, brake components and inlet manifolds without yellowing up to 325 degrees F. That makes it a fit for engine parts and other hot metal that needs a clear finish. For temperatures above that, check the product directions before you coat.
Can I use clear coat on metal?
Yes. DiamondFinish Clear can be applied direct to metal or over other coatings. Clean the metal first and follow the prep steps for your metal in the DiamondFinish Clear direct to metal guide.
Is DiamondFinish Clear flexible?
Yes. DiamondFinish Clear stays permanently flexible as it cures, which is why it takes impact without cracking off metal that flexes. The film survives 160 inch-pounds of direct and indirect impact.
Does DiamondFinish Clear yellow in sunlight?
No. DiamondFinish Clear is UV stable itself and holds 1000 hours of QUV 313B accelerated weathering without yellowing or chalking. It does not block UV from reaching the surface underneath, so a color coat under it still needs to be UV stable.
How long does DiamondFinish Clear take to cure?
It cures without heat or UV lamps at 50 to 82 degrees F. Average cure is 1 to 2 hours depending on humidity, and the film becomes hard in about 4 days and keeps hardening for weeks. Do not use UV or bake lights, because they slow the cure.
Still have questions? Search the KBS Support Desk for instant answers
Looking for more projects with KBS products? Browse the full library of KBS application guides and restoration projects or see all KBS clear coats for metal.
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