This is a 10-piece contractor pack of heavy duty - professional-grade, female, 6 ball, brass, air Quick connect couplers. Universal style interchange will adapt to the 3 most popular interchanges - industrial/M-style, automotive/truflate, and ARO styles. 6 locking steel balls for increased life and holding power. Nitrile seals for performance in extreme temperatures, and solid brass construction for high corrosion resistance and longer life. Industrial/M-style, automotive/truflate, and ARO style plugs/nipples