NFPA Conference & Expo in the USA

An equal tee (sometimes called a straight tee) is a T‑shaped fitting in which the main run and branch outlets all share the same nominal diameter.

An Equal Tee, also known as a Straight Tee, is a type of pipe fitting with three openings. It has a T-shaped design, where all three openings have the same diameter, allowing for an even flow distribution

Mechanical tees, as part of grooved piping systems, use gaskets secured by housings to attach a new line of pipe to an existing one. The mechanical force from the bolts and nuts combined with the gasket and lubricant creates a tight seal around a hole drilled into a run of pipe.