# Pololu Universal Aluminum Mounting Hub for 1/4″ Shaft, \#4-40 Holes (2-Pack)

**Type:** Product page · **SKU:** POLOLU-1993 · **Brand:** [Pololu](https://core-electronics.com.au/brands/pololu-australia)
**Page:** https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-1-4-shaft-4-40-holes-2-pack.html ([markdown](https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-1-4-shaft-4-40-holes-2-pack.html.md))

These universal aluminum mounting hubs allow you to mount custom wheels and mechanisms to 1/4 inch diameter motor shafts. The set includes two hubs, four #4-40 set screws for securing the hubs to motor shafts, and one 0.05″ Allen wrench for use with the set screws. Each hub has four threaded mounting holes for #4-40 screws (not included).

## Pricing

- **Price:** $22.30 (inc GST) — $20.27 AUD, exc GST
- **Quantity discounts:** 10+ $19.46 (exc GST) · 25+ $18.85 (exc GST)

## Availability & dispatch

- Available with a lead time — expect dispatch between Aug 17 and Aug 18.

## Description

| [![](https://core-electronics.com.au/media/remote_images/0J4989.250_b7I0DJ.jpg%3F0f02324627d2c46e4b4980873a422dee)![](https://core-electronics.com.au/media/remote_images/zoom-d0cfc0fffa825c4654893ef42b77cee3_xF9RYi.png)](https://core-electronics.com.au/#) |
|---|
| 1/4" Pololu universal aluminum mounting hub on a NEMA 23 stepper motor with 1/4"-diameter output shaft. |

These universal mounting hubs are designed to work with most 0.250 inch (6.35 mm) shafts, including round shafts and “D” shafts, such as those on Pololu's [NEMA 23 stepper motors](https://core-electronics.com.au/#). Each of the two included hubs has four mounting holes for [\#4-40 screws](https://core-electronics.com.au/machine-screw-4-40-1-2-length-phillips-25-pack.html) (not included), letting you mount custom wheels or mechanisms to your motors. The four included #4-40 hex set screws (two for each hub) allow secure coupling of shaft to hub, and a [0.05" hex wrench](https://core-electronics.com.au/hex-allen-wrench-0-05.html) (often the smallest size in SAE Allen wrench sets) is included for use with the set screws. A dimension diagram of the hub is available under the resources tab.

These hubs will work with Pololu's [NEMA 23 stepper motors](https://core-electronics.com.au/#), and they also work with 80 mm and 90 mm [Pololu wheels](https://core-electronics.com.au/#).

**Documents:**

- [Dimensional Drawing](https://core-electronics.com.au/attachments/localcontent/1993-0_6883259e90c.pdf)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/p/o/pololu_universal_aluminum_mounting_hub_for_1_4_shaft_4_40_holes__2_pack___pololu_1993__00.jpg)