All but the earliest Lamborghini Countachs came with ridiculously wide 345/35 ZR15 rear tyres. Not only does this give the rear end of the Countach a muscular squat that could rival a professional strongman, but it also means the inner barrel of the alloys are incredibly deep and hard to clean without removing the wheel first.
Barrel brushes are the only real way of cleaning the rear wheels of a Gandini masterpiece. These brushes are designed to slip effortlessly between the rim and brake disc to clean those inner barrels without having to dig out the impact wrench, allowing for the easy cleaning of a classic Lambo.
This may be an extreme example admittedly, but the inner barrel of most alloys is pretty hard to clean without removing the wheel first. This inner barrel can also become pretty mucky over time, facing the brunt of brake dust, mud and other contaminants that can eventually lead to pitting if left to fester. Pitting not only looks unsightly but is irreversible without getting your wheels professionally refurbished.
With this in mind, we've chosen our favourite barrel brushes that will keep the entirety of your alloys clean and save you refurbishing fees down the road.
The best barrel brushes for alloy wheels
EZ Detail Car Alloy Wheel and Motorbike Cleaning Brush
The best wheel barrel brush

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Hailing from the USA, the EZ Detail Brush is hands down the best way to clean alloy barrels. Made using flexible nylon bristles that are designed to not scratch finishes, this brush will dislodge embedded contaminants without risking unsightly scratches. These bristles are designed with a memory so they return to their original shape after use.
Aside from the bristles, this brush is outstanding for how versatile it is. The central stem is malleable which makes reaching behind bulky brake callipers super easy, and is also wrapped in vinyl to eliminate any scratch risk. The handle is ergonomically designed and features a welcome knuckle guard.
There are a plethora of cheaper imitations on the market, but the bristles will warp and the quality will be nowhere near the same as a proper EZ example. It may seem rather expensive for a wheel brush, but it is unmatched in its cleaning ability.
Auto Finesse Wonder Wool Medium
The best soft barrel brush

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Slightly softer than the EZ example, Auto Finesse's Wonder Wool brush is a plusher way of cleaning the inner barrel of alloy wheels. Using soft lambswool for cleaning the wheels, this brush will still cut through grime without being a scratch risk to even the most delicate of surfaces.
While it lacks a knuckle guard, the long handle should allow for some distance between your hand and any hard metal and the fact the handle is wooden adds a touch of luxury. It's also available in small and large, perfect for cleaning any type of alloy.
Meguiar's Supreme Microfibre Angled Wheel Cleaning Brush
The best angled barrel brush

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Microfibre is a wonder material when it comes to cleaning. Absorptive, non-piling and affordable, more and more companies are looking to this material for car cleaning. Meguiar's now offer this angled microfibre brush that's designed to reach awkward areas without posing a scratch risk.
While it's not as versatile as the EZ Brush, the angled head is perfect for brake discs, inner barrels and scrubbing the rear side of wheel spokes. There is no metal in its construction so need to worry about scratches and the solid plastic shaft means it's tough enough to tackle the muckiest of wheels with ease.
Chemical Guys Power Woolie Microfiber Wheel Brush with Drill Adapter
The best powered barrel brush

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For even more cleaning power, why not harness the power of electricity? This microfibre barrel brush head from Chemical Guys is designed to attach to an electric drill for a really powerful cleaning experience.
It's a fairly standard microfibre head and does without the usual ergonomic handle (well any handle) which means it's more of a specialist tool and requires a drill to be an effective cleaner. Still, it's excellent at stripping away dirt without damaging wheels and will save you time and energy.
Why you should buy a barrel brush?
Everyone knows to clean the alloy face when washing a car. Cleaning the face removes surface contaminants and makes the alloy look far cleaner but can be rather superficial compared to the inner barrels. This part of a wheel is subject to the worst detritus imaginable and can become a hotspot for corrosion over time (often called pitting).
A barrel brush will easily reach and clean these areas of a wheel which should go a long way in keeping any corrosion at bay without risking any scratch damage.
Barrel brushes can be used for more than just alloys too. Car grilles, exhausts, intricate styling features and engine bays will have their fair share of hard-to-clean nooks that a barrel brush can be used in too. Just make sure it's clean first.
What to look for in good a barrel brush:
Materials - A good barrel brush will either use nylon, microfibre or lambswool for the brush head. Which head material you prefer will depend almost purely on personal preference as all offer roughly the same cleaning abilities and require the same level of maintenance. There are a couple of technical differences, but for personal use, there isn't anything that places one above the others.
Versatility - A good barrel brush will be able to clean a multitude of areas with relative ease. Consider the styling of your alloys and if any particularly small nooks may require an even smaller barrel brush to properly clean. Also, think about the size of your brake discs and overall access, a narrow pliable brush will prove its value here.
Extras - Small extras like knuckle guards, rubber coatings and ergonomic handles can make or break whether you regularly reach for a barrel brush when cleaning or it sits unused in the shed. Anyone who's ever smacked their knuckles into an alloy wheel or accidentally left a deep scratch from an exposed bit of metal can attest to this.
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