• Used to Manufacture Dual Seal Insulating Glass Units
• Exceptional Low-Vapor Transmission
• 3/32" (2.4 mm) Diameter

CRL Polyisobutylene is used as the primary vapor seal in dual seal Insulating Glass units. It is a one-part, non-drying, non-hardening material for dual seal fabrication in either tape or slug form. Primarily used in conjunction with CRL Insulating Glass Silicone, Polyisobutylene adheres to glass and metal, and resists water, ozone, and ultraviolet light.


The tape form is hand applied to the sides of Dual Seal Spacer. Slugs are used in automated machines for application to the Spacer. CRL Polyisobutylene is made under the highest quality control conditions possible. With 100% solids content, it's compatible with any secondary seal. Each case contains 10 each 42' (12.8 m) rolls, each containing five strands per roll 210' (64 m), totaling 2100' (640 m) per case.