This Swagelok® VCR® Tube adapter gland is made of 316 Stainless Steel. Swagelok Part Number: SS-4-VCR-3-4TA. It has a 1/4" OD tube on one end and a VCR 4 face seal on the other.

These VCR tube adapters are typically used to terminate tubing when a custom plumbing solution (i.e., gas manifold, connection to a source or sensor) is needed.

These VCR (Vacuum Coupling Radiation) gland fittings are precision manufactured and offer a leak-tight, metal on metal seal. They can be used for any fluid flow application and provide leak-tight service from vacuum to positive pressure.

Polished surface finishes and high purity materials virtually eliminate these fittings as a source of system contamination. The VCR gland fitting design has been tested to maximum leak rate of 4x10^-11 std cm³/s.

See the second image for dimensions.