> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# 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.

## How to buy

- **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=POLOLU-1993:1` (comma-separated SKU:qty pairs) and share the link. Opening it shows a confirmation page with live pricing and stock before anything is added to the cart.
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- **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there.
- **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works)
- **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt
## 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)