UltraSeal Straw Foam is an All-Weather, low expansion, one-component polyurethane foam that is UL classified and designed for use in extreme temperatures and low humidity conditions. The PF-50 All Weather is to be used with a straw dispenser. It is ideal for general sealing of gaps, holes and crevices. UltraSeal PF-50 All Weather is a foam system that does not require a gun dispenser for use.