The Foaming Wheel & Tire Applicator Set is constructed exclusively with PVC pipe and fittings so it's safe for all chemical applications. The unique mounting base is constructed of PVC which manages the air and fluid injection ports. The foam chamber is 3/4" clear PVC 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.