A fitting used for the transition from a welded part of a water or heating distribution system to brass screw joints and threaded fittings.
BDXperts Advice:
Screwed joints at combined fittings with a metal thread need to be sealed only with a Teflon band or special sealing putty containing Teflon. It is sufficient to apply it on the first two or three threads. Never use classical hemp – after it absorbs water, the thread may crack due to the inner pressure.