Viega 22005 MegaPress coupling With stop Smart Connect technology Carbon steel, 3/4'' x 3/4''

Both ends of the 22005 are press connections, listed as P1 x P2, sized 3/4 inch by 3/4 inch. No threading, grooving or welding at either end, so you press it onto prepared 3/4 inch pipe with a MegaPress jaw on both sides.

The 22005 is a coupling with a stop, meaning there is an internal shoulder that sets the insertion depth so each pipe end seats the same distance. That is what you want for a normal in-line joint. Where you cannot rotate or spring the pipe apart to make up a joint, for example repairing a fixed run, a stopless (slip) coupling is the one to use instead, because it lets you slide the fitting fully onto one pipe and then back over the joint.

Carbon steel. That makes it a match for black iron and carbon steel pipe systems, not for potable water lines, where a copper or stainless press fitting is called for. Typical carbon steel MegaPress uses are gas, hydronic heating, compressed air, fire protection and similar mechanical piping.

Smart Connect is Viega's unpressed-connection feature: an unpressed fitting leaks visibly during pressure testing so it gets caught on the test rather than after the walls close up. On a job with a lot of joints, that is the difference between finding one missed press at test and chasing it later. The 22005 carries it as a 3/4 inch carbon steel coupling.