Pololu Universal Aluminum Mounting Hub for 4mm Shaft Pair #4-40 Holes

The Pololu universal aluminium mounting hub allows you to mount custom wheels and mechanisms to 4 mm motor shafts. The hubs are sold in pairs, and each hub includes one 4-40 set screw for securing a motor shaft to the hub.


Our supplier is out of stock

Our Code: MEC-30023

Supplier Link: [Pololu MPN:1081]




These universal mounting hubs are designed to work with most 4 mm shafts, including round shafts, and “D” shafts. Each hub has four mounting holes for 4-40 screws, letting you mount custom wheels or mechanisms to your motors. 4-40 hex set screws (one included for each hub) allow secure coupling of shaft to hub. The kit includs set screws and a matching 0.05" hex wrench .

Kit Includes:

  • Set screws for fixing the hub to a shaft
  • 0.05" Hex wrench to fit the set screws

The picture to the right shows a hub with Pololu’s 25:1 metal gearmotor 20Dx44L mm and a Pololu 20D mm metal gearmotor bracket. This hub will work with any Pololu 20D mm metal gearmotor.

We also stock #4-40 machine screws of various lengths that can be used to fit wheels to these hubs.

Mechanical drawing for the Pololu universal aluminum mounting hub for 4 mm shaft.