Stihl RB 400 DIRT BOSS High Pressure Washer 2700 PSI 2.7 GPMStihl RB 400 DIRT BOSS High Pressure Washer 2700 PSI 2. 7 GPM The STIHL RB 400 DIRT BOSS pressure washer features a powerful 196 cc (6. 5 hp) engine, delivering 2,700 psi of water pressure at 2. 7 gallons per minute. Its got the power you need for heavy duty cleaning of sidewalks, driveways, decks and more. The RB 400 DIRT BOSS is also built to last, including a brass manifold pump design, stainless steel valves and ceramic coated pistons. There is