The FIT56 kit contains all the air line fittings used in an HK5 or HK6 Problaster Horn Kit. Includes the following 1/4" NPT fittings: P/N 2151-145 PSI pressure switch, P/N 52175-175 PSI safety valve, P/N 52835-drain cock, 51414L elbow compression fitting. Also includes P/N 318-BK momentary push button and a vial of Juice-1 Thread Sealant.