A SIMPLE EFFICIENT DESIGN: This little workhorse sets the standard for simple, efficient design and dependable service. Moving parts are kept to a minimum, helping to keep the unit practically maintenance free. C-600P Injectors have a front mounted head and, an easy to adjust, side mounted, diaphragm stroke adjustment (feed rate control). The C-600P features Blue-White's Exclusive Heavy Duty Cartridge Valve Pump Head that resists both clogging and airlocks. The C-600P can be ordered with an optional solid state feed controller mounted directly to the pump housing. When you need to get the job done efficiently and economically, choose the CHEM-FEED C-600P.