Positive action locking mechanism so coupler cannot be detached accidentally. Extra large air passage insures greater air flow. Automatic air check valve shuts off air instantly when uncoupled, providing leak-proof seal. Corrosion-resistant steel plug and stainless steel check and check spring for long service life. Free swiveling action prevents curling or kinking of air hose.SEPTLS43811660. TLS43811660. Lincoln industrial Lincoln industrial Lincoln Style Couplers & Nipples - 11660.