CRL Medium Bronze Textured Polyurethane Exterior Sealant Cartridge

• One‑part grainy textured modified polyurethane sealant with primerless adhesion on most construction surfaces, including KYNAR® coated metals
• AAMA approved
• Low‑VOC — only 9 g/L
• UV resistant / non‑yellowing

CRL M66 (SKU: M66MBRZ) is a one‑part, moisture‑curing, gun‑grade modified polyurethane sealant formulated for moving joints in storefronts, curtain walls, perimeter framing, concrete, masonry, metal and glazing applications. It requires no primer on most common substrates and offers durable, permanently flexible performance in exterior and interior installations.

Basic Uses
CRL M66 is engineered as a low‑VOC polyurethane construction sealant for sealing moving joints between framing (door and window) and building structure, glazing toe/heel beads, and general perimeter joint sealing. It adheres exceptionally to fluoropolymer paint coatings such as KYNAR®, Duranar® and Duranar® Sunstorm™, as well as to aluminum, steel, galvanized steel, plastics, vinyl, glass, wood, brass and concrete. Compatible with insulating glass sealants when used as a toe or heel bead. Paintable with water‑based paints after two hours.

The light grainy texture blends with textured substrates (stucco, masonry) and smooth metal storefront joints to hide tooling marks and eliminate visible waviness. Also suitable for manufacturing uses including travel trailers, mobile homes and galvanized HVAC ductwork assembly.

Key Differentiators

• Exceptional adhesion to KYNAR® and other fluoropolymer‑coated metals — ideal for metal storefront and curtain wall sealing
• Ultra‑low VOC (9 g/L) and solvent‑free, qualifying for LEED EQ credit
• Permanently flexible — resists hardening with age and remains flexible at low temperatures
• Fast curing — skins over in ~30 minutes and cures ~1/8" (3 mm) per day
• Wide service temperature range after full cure: -75°F to 300°F (-59 to 149°C)

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® indoor air quality credit.
Low‑temperature gunning and application down to 0°F (-18°C).
Permanently flexible and UV resistant — will not yellow.
Tooling time: approx. 20–40 minutes (temp/humidity dependent).
Paintable with water‑based paints after 2 hours.

Technical Data & Approvals
Meets or conforms to: Federal Specification TT‑S‑