ISO Standard vacuum fitting in size NW16. Adapts NW16 to Male or Female Swagelok VCR instrument style fittings of stated size. The size NW 16 is limited to 1/8", 1/4", 3/8" and 1/2" Male and Female VCR Swagelok terminations.  This is a welded adapter. Compatible with NW, KF, QF and ISO flange standards. Manufactured generally in the USA. Some exceptions apply. This is a building block approach for creating and supporting vacuum systems to 10-6 Torr. They are fabricated and welded to a stainless steel NW vacuum port cover or stub at the factory.  Used primarily to hook up to instruments and vacuum chambers with mating, opposing Swagelok ports.