Blue Monster PTFE pipe thread sealant is formulated with PTFE resin, a polymer consisting of recurring tetrafluoroethylene monomers whose formula is (CF2-CF2). It is inert and compatible with a very wide range of materials. Use Blue Monster on threads made from all metals, PVC, CPVC, ABS and nylon plastic pipe systems. CSA (Canadian Standards Association) approved for gas. NSF (National Sanitation Foundation) approved for potable water. Non-hardening, slow-drying soft-set formula is non-toxic and grit free.