4 gallon high density polyethylene tank. Large 4.25" opening with filter basket. Shut-off valve and wand overall length of 28" for hard-to-reach places. 4' of high-pressure hose. Padded shoulder straps for greater comfort. The model 475 is capable of producing up to 60 psi, with its rugged connecting rod actuated diaphragm pump. The diaphragm is made of high quality Viton® for its resistance to harsh chemicals and abrasion and its long life expectancy. By design the diaphragm is able to pass small abrasive particles without damage to the pump assembly. The diaphragm pump is ideal for handling chemicals in wettable powder form, as well as liquid formulations.