502MS Karna-Flex Sealant

August 19, 2026 at 12:32 p.m.

502MS Karna-Flex is a rubberized thermoplastic sealant to repair leaks on ALL types of roofs including properly prepared single-ply, PVC, TPO, metal, concrete, spray-polyurethane foam, plywood, asphalt, BUR and modified bitumen. Designed for long-term performance, 502MS works on dry surfaces and even under water. 502MS can be applied in cold temperatures. Other uses include leak repairs around skylights, gutters, downspouts, pinholes in metal and to waterproof around metal roof fasteners. 502MS is easy to apply due to its’ butter-like consistency. It can be brushed or troweled.

Advantages

One component—no need to intermix with other materials
Easy application by brush or caulking gun
Superior film—forms a durable, weather resistant elastomeric membrane
Has superior adhesive and cohesive strength
Low temperature flexibility—specially selected polymers and resins impart superior low temperature properties to the coating
Adheres to wet or dry surfaces

Learn more about 502MS and find a retailer near you!

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