Trex RainEscape - Butyl Caulk 1 Tube covers about 50 lineal feet (contains 10.1 Fl. Oz.) Specifically designed for use with Trex RainEscape down spouts & troughs Part of a system that protects the space below your deck from rain, sun, and other elements Part of a system that expands your outdoor living space This caulking is necessary when encountering a surface where the sealing tape will not stick