Kapton® Discs are great for masking small areas on circuit boards. Discs come on a liner that is wound on a 3" core. Discs are made from polyimide film and a have a silicone adhesive. Silicone adhesive will not leave behind a residue. Discs can also be used for powder coating and automotive transformer manufacturing. Withstands temperatures of up to 500° F. UL510 flame retardant. Discs have a 1/4" diameter. 1 Mil thick.