Pipe Fittings

700+ products

Expected delivery: Tue, Nov 17

Pipe fittings join, branch, reduce and cap pipe in water, air, drain and gas systems. This subcategory covers elbows (45 and 90 degree), tees, crosses, couplings, unions, nipples, reducing bushings, plugs and caps. Materials include brass, black iron, galvanized steel, copper, PVC and CPVC. Connection styles include NPT threaded, sweat, solvent weld, compression, barb and push-to-connect.

What to check before you order

  • Nominal size and thread. Fittings are listed by nominal pipe size. Most threaded fittings here are NPT. Reducing fittings list the larger size first.
  • Material for the service. Black iron is commonly used for gas and compressed air, galvanized for some water and outdoor uses, brass and copper for water, and PVC for drains and cold water.
  • Pressure class. Threaded malleable iron fittings come in pressure classes such as 150 and 300. Use the class the system calls for.
  • Lead free for potable water. Brass fittings in drinking water lines should be marked lead free.
  • Male or female ends. Note whether each end is male (MNPT) or female (FNPT) before ordering an adapter.

Seal NPT threads with PTFE tape or pipe sealant from sealants and caulk. Pipe itself is under pipe and tubing, valves are under valves, and more parts are in plumbing. Air line fittings are under air fittings and couplers.

Buying guide: NPT pipe threads explained: sizes and sealing

Common questions

What does NPT mean on a pipe fitting?

NPT stands for National Pipe Taper. The tapered threads wedge together and are sealed with PTFE tape or pipe dope. NPT does not mate with BSP threads; see our thread sizes guide.

Can copper be connected directly to galvanized steel pipe?

Joining copper to galvanized steel can cause galvanic corrosion. A dielectric union is commonly used to separate the metals. Follow your local plumbing code.

Pipe Fittings: page 15

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