The Kleinn Model 330 is a premium roof-mounting hardware and fittings kit engineered to make installing roof-mounted air horns quick, easy, and completely weatherproof. Featuring a heavy-duty brass construction built to withstand harsh outdoor elements, this universal installation kit is specifically designed to secure Kleinn Model 401, 411, and 412 roof-mounted horns. The kit provides the exact required standoff height to cleanly route a 1/4" OD air line to the horn assembly from beneath the vehicle's roof, ensuring a professional, leak-free installation while maintaining optimal pneumatic efficiency and a secure, vibration-resistant mount.