Two sleeves give these fittings extra gripping power. They bite into tubing as you tighten the nut to form a strong seal. Fittings can handle pressures up to 15,000 psi. They are typically compatible with Swagelok®, Let-Lok, and Parker A-Lok fittings.

Also known as luer lock couplings, these consist of a plug and socket that connect with a half turn. Use in low-pressure applications up to 30 psi.