Features:A gear motor is a specific type of electrical motor that is designed to produce high torque.Gear motors are primarily used to reduce speed in a series of gears, which in turn creates more torque.Full metal gears would ensure a longer service life, high torque and less noise.There are three reduction gear motors of different speed and you can choose the one you need.Gear motors can be found in many different applications, and are probably used in many devices in your home.Specifications:Voltage: DC 6VSpeed: 10RPM, 15RPM, 20RPM(Optional)Outer Diameter: 12mm / 0.47"Max. Gear Ratio: 1:1000Speed(RPM)No Load Current(mA)Stalling Torque(KG.CM)101551535720458Package Includes:1 x Gear MotorNote: There might be 10% speed error. Thanks for your understanding.