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.

Use these fittings at pressures up to 9,700 psi. Also known as instrumentation fittings, they are made to tight tolerances for use in high-precision applications. They are compatible with Swagelok®, Let-Lok, and Parker A-Lok 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.