I have two sets of wheels and tires; Summer and winter. Winter wheels are optional labs with regular shredder valves. The valve covers I used to have were aluminum with colors to match the car. cool cool right? Not correct! The valve cover corrodes in the winter and sticks to the darn shredder valve and you have to get the damn thing out with pliers. Enough of this stretching and twisting and sooner or later the damn thing will break down. Also, when winter comes and the temperature drops to 20 degrees Fahrenheit and your tires are low on air and you're trying to remove the aluminum covers, good luck because those things aren't coming out. So I replaced them all with these to keep it nice and simple. Simple valve covers with O-rings to keep air and dirt out. They are a bit smaller than the factory valve caps on my summer bikes, but they fit great and cover the brass part of the stem perfectly. Plus if I lose one. I have 46 spare parts. Good for $5. Take her!