What are alloy wheel keys and how exactly do I remove my alloy wheels?

usually one lug not on each wheel has an odd shape nut and you have to stick the key in the lug wrench, and unscrew that lug nut to get the wheel off. without the key it can be time consuming and frustrating trying to get a lug nut off without damaging an expensive rim, And if you are in a hurry, or it is close to closing time on a shop late on a friday, your car may be unavailable until you find the right key for the job, It is possible to remove some lug nuts, but it takes an expert with a lot of confidence, because one slip of a power chisel designed to split nuts, can take an irrepairable chunk out of an expensive rim.