Viega 91705 MegaPress 90° elbow Smart Connect technology 316 stainless steel, 1'' x 1''

Both ends are press connections (P1 x P2), not threaded. You need a press tool with the correct MegaPress jaw or ring for 1 inch to make up the joint. No threading, welding, or soldering is involved, and there is nothing on this fitting that will accept a threaded nipple.

The 91705 is built in 316 stainless steel rather than carbon steel. 316 is the grade you specify where the medium or the environment would corrode a carbon steel fitting - wash-down areas, coastal or chemical exposure, and lines where contamination of the fluid matters. If the run is plain black iron gas or ordinary dry mechanical piping, the carbon steel MegaPress elbow is the normal choice and 316 is more fitting than the job needs.

Lay out roughly 3.961 inches on each leg and about 1.78 inches of height for the 91705. That is the fitting envelope only - you also need clearance around the pipe for the press jaw to close squarely on each socket, so a 90 tight against a wall or beam usually needs more room than the fitting dimension suggests.

Smart Connect is Viega's feature that lets an unpressed joint leak intentionally during pressure testing, so an installer can find a connection that was missed before the system is put in service. On a 1 inch 316 stainless elbow in a long run with dozens of joints, that is the difference between locating one bad press and chasing the whole line.

Viega manufactures the 91705 in Germany. That matters on public and institutional work where country of origin has to be documented in the submittal package.