90°SS Elbow (SR) means 90° stainless steel short radius elbow that the radius of curvature of the elbow is 1 times the diameter of the pipe, also called 1D.
The material of the short radius elbow is stainless steel 201.304, etc., carbon steel 20 #, 20G, etc., alloy steel 12CR1MOV, etc. GK can supply 2inch 90 degree elbow, 2.5 inch 90 degree elbow and 2 inch 90 degree elbow. Short radii are generally used in low pressure fluids or where elbows are restricted.
Also, GK can supply these pipe fittings.
long radius elbow
short radius elbow
long radius 180°elbow
side outlet elbow (right hand or left hand)
double branch elbow
Stainless quick elbow
socket welded elbow