4 Pack, 1/4" FNPT M Style Coupler, Use For Connecting Air Tools To An Air Hose Or Any Pneumatic System Components, With Corrosion Resisted Plated Brass & BUNA-N Seal, Connection 1/4" FNPT & M Style Plug, Couplers Designed To Accommodate Multiple Pneumatic Systems & Tools, Plated & Coated With Corrosion Resistant Increases Servicing Life, Sleeve Guards Help Reduce The Potential Of Accidental Disconnects & Protects The Coupler Sleeves, Includes: 4 Female M Style Couplers.