Pro-Track Silicone Coated Foam Rubber Tires - RETRO SIZE ! - 3/32" (2.37mm) Axle x 0.815" (20.7mm) Diameter x 0.800" (20.3mm) Wide - Custom Made for Professor Motor by Pro Track - Small diameter hub for best grip - Setscrew aluminum rims with 0.050" (1.27mm) Hex Setscrews OLD Part No. PT815s332