Street elbow

A street elbow (sometimes called a street ell or service ell) is a type of plumbing or piping fitting intended to join a piece of pipe and another fitting at an angle.

A regular elbow has a hub or female-threaded connection on each end, so it can join two male pipes.

They can be used in many plumbing applications, including water supply, drainage, sewers, vents, central vacuum systems, compressed air and gas lines, heating and air conditioning, sump pump drains, and other locations where plumbing fittings would be used to join sections of pipe.

For example, Canada's national plumbing code prohibits them in natural gas and propane installations:[1] Street elbows and tees are not permitted because these fittings have both male and female threaded ends.

When the connection is backed off to align the piping, leakage may result.