316 stainless steel. Designed for connection to RJT union. Enables a hose connection into hygienic pipe systems. . RS 265-4542: 1 inch bore, 89 mm length. RS 265-4558: 1 1/2 inch bore, 95 mm length. RS 265-4564: 2 inch bore, 98 mm length. RS 265-4586: 3 i