Simple and mechanical design is easy to understand. Two valve body designs: one for downflow regeneration and one for upflow (covers every valve in the 5600 family- quick access to all internal components). Injector/drain modules containing the brine vailve, flow controls and injector are removal from the valve's exterior. Ruggedly built timer is designed with heavy duty 3/8 wide plastic gears. 5600 controls are user friendly and easy to program. Choice of 7 or 12 day clock or demand regeneration with either mechanical or electronic meter. Economical-small annual power consumption; keeps the time and activate the piston/valve mechanics with a single motor. Designed with double backwash.