Blackstone's positive displacement solenoid driven pumps use a minimum number of moving parts, therefore reducing the chance of mechanical failure. Part wear and oiling associated with motor driven pumps (ball-bearings, gear drives and camicrosecond) are not a concern with these pumps. Blackstone pumps are more accurate than standard pumps due to the positive displacement design ensuring each stroke is identical to the strokes before and after it, thus keeping the flow rate consistent. Each pump is supplied with discharge and suction valves. Blackstone pumps are equipped with a single control for pump output. The external flow rate control (potentiometer) on the face of the pump allows you to adjust the percentage of flow from 0 to 100 of the pump's rated capacity. This feature eliminates the need to worry about stroke lengths and power settings. An LED indicator lights up each time a stroke begins, allowing the user to assess the stroke rate from a distance. Blackstone pumps are supplied with the highest quality material as standard equipment-not optional. The diaphragm utilizes one-piece construction of PTFE, which unlike conventional laminated diaphragmicrosecond, will stand up to the test of time and wear. Ball valves are constructed in glass. The pumphead and O-rings are made of PVDF, PTFE and FPM/FKM which offer unsurpassed resistance. The chemical resistance chart (right) shows how well PVDF and PTFE stand up to some of the most aggressive chemicals. Blackstone pumps are completely sealed during assembly and offer IP65 protection against splashes and spills providing excellent protection even in hostile environments. The fiber-reinforced polypropylene housing stands up to aggressive chemicals while offering superior strength under tough industrial conditions. Fiber-reinforced polypropylene pump casing. Approximately 200 W max power consumption. 0 to 50 degree C; RH max 95 percent non-condensing environment. Pressure: 7.4 psi. Flow rate: 18.3 LPH.