Micro Metal Gearmotor (Extended back shaft) - 20:1

Jargon buster

Plain-language definitions for the technical terms used above.

DC

DC means direct current, where electricity flows in one constant direction, as supplied by batteries, USB ports and many plug-pack power supplies. When a product specifies DC, it runs from a DC supply rather than mains AC, so you need to provide the correct voltage and polarity.

encoder

An encoder is a sensor that converts the rotation or position of a shaft, knob or dial into electrical signals, reporting movement as incremental steps and direction, or as an absolute position. It is used to track how far something has turned, which matters for precise positioning, speed control, repeatable movement, or using a rotary knob as an input.

kg·cm

A torque unit often used for hobby servos, meaning how many kilograms of force the servo can hold at a 1 cm arm length. A higher kg·cm rating means the servo can move or hold heavier loads, but power supply current needs may also increase.

Stall torque

The maximum twisting force a servo can produce when its output is held still and cannot move. It helps you judge whether the servo is strong enough for a robot joint, steering linkage, or other load.

Torque

A twisting force that causes something to rotate, usually measured in newton-metres or kilogram-centimetres. It matters when choosing motors, servos, gears, and tools because higher torque is needed to lift heavier loads, turn larger wheels, or move mechanisms without stalling.