Pressure-assisted (non-clogging) media blaster. (nicknamed R2D2) Constructed from a used water bladder pressure tank. Peformance is great. The media tank is under low pressure to push the media out of the tank and out to the nozzle, where it mixes with higher pressure air from the compressor. Plumbing parts include a pressure regulator and an air dryer as well as various pipe fittings. The blaster rolls on a tri-cycle running gear consisting of two fixed and one swivel caster each rated at 330 pounds.