Adapts from 1/2" CPVC to 1/2" male metal pipe thread and features lugs for fastening. Used on tub and shower faucets toadapt from 1/2" CPVC riser to shower arm. Sometimes called a Drop Ear elbow. Hand tighten only; seals by means of a special elastomeric gasket to ensure leakproof seal, use of joint compound or Teflon tape is neither necessary or recommended.