Teflon thread sealing tape that can be used on iron stainless steel copper brass plastic glass or rubber pipes. This tape is a necessity if you are a plumber pipefitter or mechanical contractor--a must for any tool box. United Tape s UT-11 withstands alkalines acids hydro-carbons solvents refrigerants and gases. The UT-11 Teflon holds under extreme temperatures from -400 to 550 degrees Fahrenheit. Note: Not suited for petroleum based applications.