Features: Performance: With anti blocking and anti burning protection function, with waterproof function. CNC precision gear, it is more wear-resistant and not easy to break and sweep teeth. Stainless steel gear high torque for RC car, crawler and robot. Great choice for university professors and students who are interested in developing software for robot parts. If there are any problems, please contact our store in time. Specifications: Item: 20KG Digital Servo Operating Voltage: 4.8 ~ 6.8 DC Volts Dead Brand: 3mus Weight: 60g Motor Type: DC Motor Gear Type: Stainless Steel Gear Working Frequence: 50-333Hz Operating Travel: 180degPWM 500-2500mus Size: 40 * 20 * 40.5 mm Package Information: Package Size: 6*4*4cm Package Weight: 130g Plastic Package Package List: 2* 20KG Digital Servo 2* 25T Servo Arm