> **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 Wheel for Micro Servo Splines (20T, 4.8mm) - 40×7mm, White, 2-Pack **Type:** Product page · **SKU:** POLOLU-4909 · **Brand:** [Pololu](https://core-electronics.com.au/brands/pololu-australia) **Page:** https://core-electronics.com.au/pololu-wheel-for-micro-servo-splines-20t-4-8mm-40-7mm-white-2-pack.html ([markdown](https://core-electronics.com.au/pololu-wheel-for-micro-servo-splines-20t-4-8mm-40-7mm-white-2-pack.html.md)) These white plastic wheels have silicone tires and measure 40 mm (1.57") in diameter. They mount onto micro servo splines with 20 teeth and a 4.8 mm... ## Pricing - **Price:** $9.70 (inc GST) — $8.82 AUD, exc GST - **Quantity discounts:** 10+ $8.46 (exc GST) · 25+ $8.20 (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-4909:1` (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. - **Verify the cart first:** fetch `https://core-electronics.com.au/cart/link/POLOLU-4909:1.md` for live line prices (inc & exc GST, quantity discounts applied), stock and dispatch estimates, and totals. Append `/to/{AU-postcode}` (or `/to/{country-code}:{postcode}`) before `.md` for delivery options and prices to that destination. Unknown, retired, or out-of-stock SKUs are flagged. (Query form `cart/link.md?items=...` also works but some robots parsers refuse query strings here.) - **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 These wheels are great for robotics, custom RC vehicles, or any other project you need to get rolling. They measure **40 mm (1.57")** in diameter and are designed for use with micro servos with **4.8 mm diameter** splines with **21 teeth**, such as FEETECH’s [FS90R micro continuous rotation servos](https://core-electronics.com.au/feetech-fs90r-micro-continuous-rotation-servo.html) and [FT90R digital micro continuous rotation servos](https://core-electronics.com.au/feetech-ft90r-digital-micro-continuous-rotation-servo.html). The combination can serve as a small, inexpensive, and easy-to-control drive system for a miniature robot. The wheel presses onto the servo spline just like a typical servo horn, and the small screw included with the servo accessory pack for mounting servo horns should be used to hold the wheel in place. The included silicone tires are also [available separately](https://core-electronics.com.au/silicone-tire-pair-for-40-7mm-pololu-wheels.html). **Product specification update (16 Nov 2021):** The original product name and documentation for this wheel incorrectly said it was intended for splines with 20 teeth when it really is intended for servo splines with 21 teeth. Pololu have now corrected this in Pololu's documentation. Nothing about the product itself or its compatibility with Pololu's FS90R and FT90R servos has changed. **Dimensions** | Size: | 40 × 7 mm | |---|---| | Weight: | 4.5 g[1](https://core-electronics.com.au/#note1) | **General specifications** | Shaft type: | 21T, 4.8 mm diameter servo spline | |---|---| | Color: | white | **Identifying markings** | Molded part dev codes: | whe10a | |---|---| **Notes:** 1 Per wheel, including tire.**File downloads** - **[Dimension diagrams for Pololu Servo Wheels](https://core-electronics.com.au/attachments/localcontent/pololu-servo-wheel-dimensions_119899fe413.pdf) (1MB pdf)** This file contains dimension diagrams for the 40×7mm, 60×8mm, 70×8mm, and 90×10mm Pololu Servo Wheels. - **3D model of Pololu Wheel for Micro Servo Splines 40×7mm (2MB step)** ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/i/m/image_11829.jpg)