Most Oxygenics products are WaterSensecertified meaning you dont have to worry about water regulations PSI pounds per square inch measures water pressure while GPM gallons per minute measures the flow rate of the washer This product performs at 20 GPM at 80 PSI resulting in supercharged pressure with minimum flow rate which translates to more savings on your utility bills and more money in your pocket No tools required for a seamless installation process Includes metal base and nonstick internal components for additional durability