3M Polyurethane Sealant 540 is a white, 310 mL cartridge sealant designed for sealing metal surfaces in construction, general industrial, and transportation industries. It has a maximum operating temperature of 194°F and a full cure time of >3 mm/24 hr. With a hardness of 40 Shore A and a tensile strength of 250 psi, it provides strong and durable adhesion. Application temperature ranges from 5 to 35°C, and it can withstand temperatures as low as -40°C.