Swagelok SS-400-6 gaugeable tube fitting, union, 1/4 in. tube outside diameter. Body in 316 stainless steel with Swagelok two-ferrule (back-ferrule/front-ferrule) mechanical grip end connections providing a leak-tight, gaugeable in-line tube-to-tube connection on instrumentation and fluid-system tubing. End connections: 1/4 in. Swagelok tube fitting both ends. Not bored through. Supplied with Standard Cleaning and Packaging (SC-10). Working pressure and temperature ratings are determined by the selected tubing per Swagelok catalog MS-01-140; use with correspondingly sized, fully annealed 316/316L stainless steel tubing.