It is a long, flexible, fully wire-cored brush wrapped in soft synthetic filaments, so it bends into a wheel barrel and cleans the back of the spokes and the inner rim, which is where brake dust actually accumulates. Nothing metal is exposed at the tip because the core is capped, so it will not scratch the finish as it flexes. It is the standard answer for cleaning inside a wheel without removing it.

Buy the large one for wheel barrels and the mini for tighter work: motorbike wheels, small alloys, grilles, exhaust tips and engine bay areas where the long brush cannot manoeuvre. Most people who clean their own wheels properly end up with both, since the large brush reaches the barrel and the mini handles the areas around the hub and behind the spokes. The GO EZ Brush is the compact version for quick jobs.

Used properly, no. The wire core is capped and enclosed, the filaments are soft, and the brush is designed to flex against a finish rather than scrub it. The two sensible precautions are to rinse the wheel first so you are not dragging grit around the barrel, and to check the tip cap regularly, since a worn or missing cap exposes the core. Replacement tips are available for exactly that reason.

Rinse it thoroughly after every use, because leaving wheel cleaner in the filaments shortens their life and leaving brake dust in there means you carry it back onto the next wheel. Shake it out and hang it to dry rather than standing it on the filaments, which bends them permanently. Keep it for wheels only and never use it on paint. If the tip cap wears through, replace the tip rather than continuing to use it.