The SG90 has 3 wire interfaces in which the connections should be made as follows: Red wire-5V, Brown Wire-Ground, Yellow wire-digital pin 9. Operating speed: 0.12second/ 60degree ( 4.8V no load) ; 0.10 seconds / 60 degrees (6.0 V) Stall Torque (4.8V): 17.5oz /in (1kg/cm) Operating voltage: 3.0V~ 6V Temperature range: -30 to +60 Dead band width: 7usec No Load Running Speed: 0.090.01 sec/60 at 4.8V Rotary Angle: 180 9G micro servo motor for rc robot, robot arm, helicopter airplane, car, boat remote controls and ardu&ino experiments. Package Include: 12 X SG90 servo motor 12 X servo arms and screws kit.
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