The GP-3A grout pump is an air-powered using only 3 cfm of compressed air at 50 psi, this model uses an air cylinder and pneumatic air logic block to control the pumping action. Controls on the pump include a pressure regulator and an adjustable speed control. Maximum output capacity is five gallons per minute and the net weight is only 27 pounds. The supplied standard grout placement hose is 1 �" ID by 5� long clear vinyl tubing with a polished interior and rigid straight steel tube in the end. Kenrich GP-3A Air Operated Grout Pump Features and Benefits: Cementitious Grout Pump - Pumps non shrink sand based cementitious grouts. Air Operated - needs an air power source. Low Pressure - 15 psi max. - Ideal anywhere high pressure is not required.