This AR Pump (RMW25G28-EZ-SXPKG) is for vertical gas engine driven units. This unit is 2.5 GPM at 2,800 PSI and spins at 3,400 RPM. This pump mounts directly on to the engine shaft by using a keyed hollow shaft connection system. The mounting flange provides a convenient connection to most 7/8 diameter shaft vertical gas engines in 4 - 7 HP and fits most OEM carts. The pump includes a built-in pressure control valve, downstream chemical injection system, EZ start valve and thermal relief valve.