RECOMMENDED The last time we tested wheel polishes (in Issue 875), this Muc-Off product was part of a £30 pack, which prevented it from winning. Now, you can buy it separately – and it’s still just as impressive. The Silica Wheel Seal was clearly still working at the end of our test, and the area took little effort to come up clean. But it emits a potent chemical smell, and as it’s a liquid, application is a little tricky.