VEXpro Traction Wheels and Tread - VEXpro 217-2588, These traction wheels from VEXpro are designed to offer the ultimate in versatility and performance. They include the VersaKey mounting system, which ensures each sprocket, hub, and gear is perfectly piloted - ruling out wobbly sprockets.Each traction wheel is supplied assembled in 1in wide configuration and includes all the hardware required for 1.5in and 2in wide configurations. Sprockets are screwed into captive 8-32 standoffs, allowing for easy removal and replacement of sprockets without disassembling the entire wheel. No more worrying about the whole wheel falling apart just because you wanted to remove a sprocket. VEXpro 217-2588 4\" Traction Wheel