1High Torsion, Low Noise: 36mm good quality steel pipe electricity, possess small size, low noise, high torsion and long life 2Ball Bearing Design: Gear motor adopt ball bearing design, enhances shaft friction resistance, very practical 3Multi Function: Built in sensory drive function, free switching function of CW and CCW, wire control brake function, pulse width PWM speed control function, FG signal speed measurement function 4Over Current, Voltage and Temperature Protection: Over current protection function for 3A, over voltage protection function for 30V, over temperature protection function for 80 5Automatic Start Function: Electric gearbox motor come with locked rotor protection, and automatic start functionItem Type: Gear Motor Material: Zinc alloy, copper, steel Uses: Industrial Shaft Length: Approx. 15mm / 0.6in Shaft Diameter: Approx. 8mm / 0.3in(D shaped shaft) Gear Box Size(length x width): Approx. 58 x 40mm / 2.3 x 1.6in Motor Diameter: Approx. 36mm / 1.4in Cable Length: Approx. 280mm / 11in Operating Voltage: DC 12V Reduction ratio (change ratio) 17 31 50 100 200 290 500 No load speed(rpm) 235 130 80 40 20 14 8 Rated torsion(Kg.cm) 2.5 4.5 7.3 30 29 10 60 Rated speed(rpm) 180 100 60 30 15 10 6 Maximum torsion(Kg.cm) 4.3 8 12.5 25 51 70 70 1 x Gear MotorThe maximum bearing capacity of the gear is 70KG, it is forbidden to block up, which is easy to burn the motor if it is blocked for a long time.