Equip your vehicle's air horn installation with the Kleinn FIT12 complete plumbing and fitting kit, specifically engineered to contain all the essential airline fittings utilized in HK1 and HK2 ProBlaster horn systems. Engineered for universal application and maximum pneumatic reliability, this premium component package includes a comprehensive set of heavy-duty 1/4-inch NPT brass fittings to ensure a leak-free setup under high pressure. The high-performance kit comes equipped with a part number 2121 120 PSI automatic pressure switch, a part number 52145 145 PSI safety relief valve, a part number 52835 air tank drain cock, and a 51414L elbow compression fitting to streamline your airline routing. Designed for a clean, professional, and comprehensive installation, this complete package also includes a part number 318-BK black momentary horn push-button switch alongside a vial of Kleinn's exclusive Juice-1 liquid thread sealant, providing everything needed to service, upgrade, or finish your onboard air system right out of the box.