Descriptions:    Stepper motor, also known as pulse motor, based on the most basic principle of electromagnet, it is a free rotation of the electromagnet, the action principle is to rely on changes in air gap to produce electromagnetic torque.Features:1. Excellent loadability. Its speed is not affected by the size of the load2. Easy to control. Stepper motor is "step" as a unit of rotation, the digital features more obvious.3. The whole structure is simple. The speed motor converts the speed into a voltage and passes it to the input as a feedback signal. The speed motor is a kind of auxiliary motor. Specifications:Voltage: 12-24VCurrent: 1.3APower Supply: DCHold Torque: 28N.cmLead: 8mmStroke: 285mmPackage Included:1 x 42 stepper motor(with 300mm screw)