iFLIGHT( iS307-3.7G) 3.7g Micro Servo Technical Data: Operating Voltage: 4.8v ~ 6.0v Operating Speed: 0.10sec/ 60° Stall Torque: e0.7kg Dimentions: Size: 19.8x8.0x22.5mm Weight: 3.7g No Ball bearing, MOS-FET Drive