This roll of white, Petro-Tape sealant is made of pure, virgin polytetrafluoroethylene (PTFE) which is impervious to steam, saltwater, air, refrigerants, fuels, acids and alkalis, and solvents and gases. It is suitable for threaded pipe connections, valve stems, hydraulic pressure lines, and lines carrying fuels, acids and alkalis, solvents and gases. It is 540 inches long, 1/2 inch wide, and 3 mil thick. It has a liquid pressure range of 2,000 PSI and a temperature range of -400 Degrees F to 50