Plumbers Putty and Sealers

Sealants, thread sealants and fillers: PTFE thread seal tape, Blue Monster and similar pipe thread sealants, DAP silicone and advanced hybrid sealants, ALEX Plus spackling, and gap-filling foam sealant. Tape and pipe dope both seal tapered pipe threads and are not both right everywhere — tape is clean and fine for water, dope fills better on older or imperfect threads and stays workable, and neither belongs on a compression or flare fitting, where the seal is metal to metal and sealant only hides a bad joint. Silicone will not take paint; an acrylic latex or hybrid sealant will, which is what decides most interior trim and window work. Check the cure and the service temperature before using any of these on gas, potable water or anything hot.