The Pololu 172:1 Metal Gearmotor 25Dx56L mm LP 6V is a compact and efficient motor solution, featuring a low-power, 6-volt brushed DC motor integrated with a precise 171.79:1 metal spur gearbox. This cylindrical gearmotor has a diameter slightly less than 25 mm, making it suitable for applications requiring a small form factor. The D-shaped output shaft, measuring 4 mm in diameter, extends 12.5 mm from the gearbox face plate, providing a reliable connection for various mechanical components. This model is also available with an integrated encoder, enhancing its versatility for projects that require feedback on motor position or speed.