CRL 777 Butyl Rubber is a unique, butyl-based sealant specially formulated using a blend of age resistant polymers to give excellent weathering properties at various temperature extremes. CRL 777 offers excellent adhesion to most clean surfaces, and will withstand joint movement of ± 10% without affecting its water-tightness. It also has a special ultraviolet fighting agent for exceptional service life.

Basic Uses
Recommended for exterior applications, CRL 777 Butyl Rubber Sealant features excellent adhesion to wood, masonry, glass, concrete, some plastics, and metal surfaces. Hidden areas, such as under sill cans, thresholds, and around screw heads are excellent applications. Other areas, such as between metal building panels, wall-mounted air conditioning units, under aluminum siding and gutters are all good applications for proven butyl sealants. Application temperature range is 40° to 120°F (4° to 49°C). Service temperature range is - 20° to 200°F (-29° to 93°C). Paint time is 24 hours.

Comparable Sealants
CRL: 888. Adco: B-100, AP-77. DAP®: Butyl Flex. OSI®: SBR-100. Pecora®: BC-158. PTI: 757. PSI: 301. Tremco®: Butyl Sealant.

Technical Data
Meets Federal Specifications TT-S-001657, Type 1, TT-C-1796A, ASTM C 1311, and AAMA 808.3-05; USDA Certified.

Limitations
Not recommended for use in sealing horizontal decks, patios, driveways or terrace joints where abrasion or physical abuse is encountered. Not recommended for use in window glazing applications or hidden joint details, which require a non-skinning, non-hardening sealant. CRL 777 has a solvent based curing system. A slight odor of mineral spirits will be detected during application, which is normal. Do not use where this odor may be objectionable, such as refrigeration units that will be stocked soon after construction. Check cartridge label and Specification Data Sheet for additional limitations. NOTE: All colors are available in bulk packaging.