The Kleinn FIT9-SLIM installation kit contains all the essential air line fittings utilized in an HK9-SLIMLINE Problaster Horn Kit, providing a comprehensive hardware solution for a clean setup. This premium kit includes high-quality 1/4" NPT fittings such as a P/N 2151 145 PSI pressure switch, a P/N 52175 175 PSI safety valve, a P/N 52835 drain cock, a P/N 51238 compression fitting, and a P/N 50040 hex plug. For a complete installation, the package also comes equipped with a P/N 318-BK momentary push button horn switch and a vial of high-performance Juice-1 Thread Sealant to ensure entirely leak-free connections throughout your air system, making it the ultimate all-in-one upgrade to ensure your horn system operates at peak performance and reliability.