Thread seal tape (also known as PTFE tape, Teflon tape, or plumber's tape) is a polytetrafluoroethylene (PTFE) film tape commonly used in plumbing for sealing pipe threads. The tape is sold cut to specific widths and wound on a spool, making it easy to wind around pipe threads.

Standard PTFE tape is quite versatile and is used to seal water, gas, and air from leaking through threaded connections, most effective on high-pressure lines. However, there are also specialty thread seal tapes geared towards a specific task or need.