Also known as KF, QF, and NW fittings, these fittings are for high-vacuum applications, such as vacuum coating and heat treating, leak testing, and analyzing gases.

Polished to a 15 Ra and under finish, these fittings have a mirror smooth interior. They are also known as ultra-high-purity fittings.

Create access points in ultra-high-vacuum lines or chambers by bolting two same-size flanges together with a copper gasket between them. The flanges’ sharp edges dig into the copper gasket and form an extremely tight seal, which means they handle higher vacuum pressures than other high-vacuum fittings with rubber gaskets.

An alternative to bolt-together fittings, these handle larger tube OD sizes and have higher vacuum ratings than quick-clamp fittings. Also known as ISO-K high-vacuum fittings, the clamps have claws that grab hold of fittings with flanged ends.