Koolance PMP-450S Pump, ID 13mm (1/2in) The reliable PMP-450S is Koolance's highest-flow 24V pump which can also run at 12V. (If pump speed will be externally throttled from 12V or 24V, PMP-450 is recommended for smoother operation.) Maximum Flow Rate: 12L/min (3.2 gal/min) @ 12V, 20L/min (5.3 gal/min) @ 24V. Maximum Head Pressure: 3.2m (10.5ft) @ 12V, 6m (19.7ft) @ 24V. Motor: Brushless DC, electronically commutated, spherical motor. Power: 8-24VDC, 3-50W, 0.13-2.1A.