This is a set of four DE Racing Buggy Tire Spikes in Blue. These quick and simple to use tools allow you to organize and ID your tires by tread, wear, and compound. No more fumbling or guesswork regarding tire sets and no more lost tires. Simply slide the stix through the stack of wheels and zip the retainer down to hold it all together. To release, just squeeze the retainer and slide off. It's so easy you'll wonder how you ever raced without them.