Wash Works' Heavy Duty A-Frame Foaming Wheel & Tire Applicator System is machined from one solid block of schedule 80 PVC and uses all PVC and Viton fittings, so it's very durable and also safe for all chemical applications. The foam chamber is 3/4" diameter and the PVC applicator head is uniquely machined with dual nozzle ports, each port holds a multi-directional foam nozzle to supply a thick lather of tire/wheel cleaning solution. Comes with a Foam Hydrominder/Pump Dilution Station, 24VAC solenoid valve, a 32" wide, safety orange, ramped treadle to acitvate the system, and a 24VAC off delay relay timer with a terminal base and electrical enclosure. A must have item for any tunnel car wash!