Viega 91635 MegaPress tee Smart Connect technology 316 stainless steel, 1'' x 1'' x 3/4''

The 91635 MegaPress tee is a reducing tee sized 1 inch x 1 inch x 3/4 inch, so the run is 1 inch on both ends and the branch drops to 3/4 inch. All three ends are press connections (P1 x P2 x P3), not threaded or sweat, so you press it onto the pipe with a MegaPress jaw set in the matching sizes.

It is 316 stainless steel, not carbon steel. That matters if you are running the line in a corrosive or washdown environment, or on a system where carbon steel MegaPress would be attacked. 316 is the molybdenum-bearing grade, so it holds up better against chlorides than 304.

Mixing stainless and carbon steel in the same line puts dissimilar metals in direct contact, which invites galvanic corrosion at the joint. The 91635 is a 316 stainless fitting and is meant for stainless systems. If your pipe is black or galvanized carbon steel, order the carbon steel MegaPress tee in the same 1 x 1 x 3/4 configuration instead.

Plan on an envelope of 5.256 inches by 3.287 inches by 1.78 inches for the fitting body. Remember you also need clearance around the circumference for the press jaw to close, which is usually the limiting factor in a joist bay or chase rather than the fitting itself.

Smart Connect is Viega's unpressed-connection feature: an unpressed joint leaks deliberately during pressure testing so you find the one you missed before the walls close. On a tee like the 91635 you have three separate press joints to make, which is exactly where a skipped press happens. Test the system and watch for weeping at each of the three ends.

No heat and no threading. All three outlets are press ends, so installation is cut, deburr, mark depth, and press with the proper jaw. That makes it workable in occupied buildings and anywhere a hot work permit would otherwise be required.

The fitting itself weighs 0.906 lbs, so it adds almost nothing to the run. Support spacing should be driven by the pipe and the fluid it carries, not by this tee.