CRL M66 White Polyurethane Construction Sealant Sausage Pack

• One-part grainy textured modified polyurethane sealant with primerless adhesion on most construction surfaces, including KYNAR® coated metals (SKU: M66S0FW)
• AAMA approved
• VOC compliant — only 9 g/L (chemically curing < 3%)
• UV resistant / non-yellowing

CRL M66 is a one-part, moisture-curing, gun-grade modified polyurethane construction sealant designed for moving joints. It provides durable, permanently flexible performance and typically requires no primer on common substrates. Ideal for storefront and curtain wall perimeter joints, M66 bonds to KYNAR®, Duranar®, and Duranar® Sunstorm™ fluoropolymer coatings as well as metal, aluminum, steel, galvanized steel, plastics, vinyl, glass, wood, concrete, brass, and other common building materials.

Basic Uses
Formulated to outperform traditional VOC solvent polyurethanes for sealing moving joints in concrete, masonry, metal, and perimeter joint applications. Use for all joints between framing (door and window) and building structure to ensure watertight installations. Compatible with insulating glass sealants when used as a toe or heel bead. Suitable for both exterior and interior use and for manufacturing applications (travel trailers, mobile homes, galvanized HVAC ductwork). Rated for service temperatures from -75°F to 300°F (-59°C to 149°C). Paintable after 2 hours with water-based paints.

The light grainy texture blends with textured substrates like stucco and masonry and helps hide tooling marks in smooth metal storefront joints for a cleaner finished appearance.

FEATURES
Exceptional adhesion to KYNAR® coated metals.
VOC compliant — only 9 g/L (chemically curing < 3%).
Eco-friendly: solvent-free, isocyanate-free, qualifies for LEED® EQ indoor air quality credit.
Low-temperature gunning and application above 0°F (-18°C).
Service temperature: -75°F to 300°F (-59°C to 149°C).
Permanently flexible — resists hardening with age and remains flexible in low temperatures.
Fast cure — skins over in ~30 minutes; cures ~1/8" (3 mm) per day.
Tooling time: approximately 20–40 minutes, depending on temperature and humidity.
Paintable with water-based paints in about two hours.
UV resistant — will not yellow from sun exposure.

Technical Data
CRL M66 conforms to and passes Federal Specification TT-S-00230C, Type II, Class A; ASTM C920-98 Type S, Grade NS, Class 25 (Use NT, M, T, A, G, O); plus ASTM C510, C639, C661, C679, C717, C719, C793, C794, C1183,