Specification: Type: BM3720A-KV650KV (rpms per volt):650 No load current:1.7 A @10 V Resistance:0.053ohms Watts:up to 630 Continuous Current:42 A Max Burst Current:55A, 10seconds Cells:34S Li-Po Recommended Props:9x 7.5 to 12x 7 Slots, Poles:12, 14 Diameter:38 mm Diameter of Shaft:5.0 mm Weight:125g Brushless ESC:50 A Motor outer diameter: 37mm Stator thickness: 20mm Package included:1 x Detrum BM3720A-KV650 Brushless Motor for RC Airplane Spare Part