BMS-390DMH High Performance Digital Servo (Extra Strong) 5.4kg / .11sec / 22.5gSpecification: Weight: 22.5 grams / 0.79 oz. Dimensions: 29 x 13 x 30 mm / 1.14 x 0.51 x 1.18 inch Torque @ 4.8V: 4.6 kg/cm , 64 oz/in Torque @ 6.0V: 5.4 kg/cm , 75 oz/in Speed @ 4.8V: 0.14sec / 60 deg at no load Speed @ 6.0V: 0.11sec / 60 deg at no loadHigh performance servo recommended for Airplane & Helicopter (Tail)