The 400B Series offers proven technology that combines the attributes of an air operated diaphragm pump with the convenience, portability, and efficiency of an electric driven design. The 400B uses less power than other conventional chemical pumps for maximum efficiency. Direct Current (DC) input for those applications out in the field. The One-Way Valve Feature inherently conforms to the EPA's 2011 mandate requiring that package designs don't allow back filling of totes or drums. This unique design improves fluid-handling capabilities with low material sheering, solids handling up to 1/10" and dry-run capabilities. The Power Distribution is a unique reciprocating, spring driven, double diaphragm configuration retains constant pressure, regardless of the load. Motor amperage is actually reduced as back pressure increases. No Internal Bypass required - the pump automatically goes neutral when the end of hose valve is shut off.