Specification: Model: C4240 KV: 890 Shaft: 5.0mm Max A: 41 Max Watt: 910 Efficiency: 80% Thrust/g: 1300-2000 Propeller: 9" / 10" Weight: 248g Lipo: 7.4V-22.2V Package Content: 1 x C4240/10 KV890 motor