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Pololu Universal Aluminum Mounting Hub for 4mm Shaft, M3 Holes (2-Pack)
These universal aluminum mounting hubs allow you to mount custom wheels and mechanisms to 4 mm diameter motor shafts. The set includes two hubs, two M3 set screws for securing the hubs to motor shafts, and one 1.5 mm Allen wrench for use with the set screws. Each hub has four threaded mounting holes for M3 screws (not included).
We have an assortment of universal mounting hubs available, spanning several shaft sizes and featuring mounting holes threaded for metric or imperial screws:
Alternatives available with variations in these parameter(s): shaft diameter mounting hole size Select variant…
Description | Specs (4) | Pictures (3) | Resources (2) | FAQs (0) | On the blog (0) | Distributors (57) |
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Overview
These universal mounting hubs are designed to work with most 4 mm diameter shafts, including round shafts, and “D” shafts. Each of the two included hubs has four mounting holes for M3 screws (not included), letting you mount custom wheels or mechanisms to your motors. The two included M3 hex set screws (one for each hub) allow secure coupling of shaft to hub, and a 1.5 mm hex wrench is included for use with the set screws. A dimension diagram of the hub is available under the resources tab.
Pololu Universal Aluminum Mounting Hub family
We have an assortment of hubs available for various shaft sizes and with different mounting hole thread options. Each Universal Mounting Hub is compatible with a variety of our wheels as detailed in the following table:
Pololu Universal Mounting Hubs | |||||||||||||
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for 3mm shafts | for 4mm shafts | for 5mm shafts | for 6mm shafts | for 1/4″ shafts | for 8mm shafts | ||||||||
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M3 holes #4-40 holes #2-56 holes |
M3 holes #4-40 holes |
M3 holes #4-40 holes |
M3 holes #4-40 holes |
M3 holes #4-40 holes |
M3 holes |
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![]() Pololu Wheels for 3mm Shafts |
32×7mm | – | – | – | – | – | – | ||||||
40×7mm | – | – | – | – | – | – | |||||||
60×8mm | – | – | – | ||||||||||
70×8mm | – | – | – | ||||||||||
80×10mm | |||||||||||||
90×10mm | |||||||||||||
![]() Pololu Wheels for Servos |
40×7mm | – | – | – | – | – | – | ||||||
60×8mm | |||||||||||||
70×10mm | – | – | – | ||||||||||
90×10mm | – | – | – | ||||||||||
![]() Pololu Multi-Hub Wheels |
80×10mm | – | – | – |
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