Eliminate drips and leaks at threaded pipe connections with Christy's Ultra Seal thread sealant. Unlike others, it is safe for both metal and plastic pipe connections. Use for plumbing, irrigation, DWV, pool/spa and other threaded water pipe connections. The sealant contains PTFE which lubricates the threads as it seals, making assembly faster and easier. Unlike using white PTFE tape, Ultra Seal won’t add to the wedging force of the tapered threads that can sometimes crack the fitting.