Type: A2208/8 No. Of cells:2-3 Li-Poly, 6-8 Ni-Mh/Ni-Cd RPM/V:2600 RMP/V Max. efficiency:78% Max. efficiency current:8-15A (>74%) No load current / 10 V:1.3 A Current capacity:20A/60 s Internal Resistance: 62 mΩ Dimensions:27.5x26 mm Shaft diameter: 3.17 mm Weight:36g /1.27 oz