This is a pair of Pin Point Buggy Rear Carpet Tires. Pro-Line now offers the popular Pin Point rear tire in the softer Z4 compound! Z4 compound is perfect for U.S. style carpet tracks and will provide more overall grip than Z3 compound. The Pin Point has tons of Ultra-Sharp Pins in a unique Sine Wave pattern that grip the carpet better than Velcro®. This new Z material provides the superior grip on a variety of surfaces used indoor (carpet, wood, cardboard, plastic, etc.). Don't get Rug-Burned by using the wrong Carpet tire; be on Point with the fastest carpet tire yet - Pro-Line's Pin Point!