SET OF TWO: Electric Bike Tire Size 12x2.125 Fits on Razor, Baja, Schwin stingray , Sun-L , X-treme SET OF TWO 12x2.125 Front or Rear DOT Approved Tube Type Tire Rim Size 12". Model P158 Recomended tire pressure 36 PSI (250 KPa) cold. Tire Inner diameter: 12 inches. Heavy Duty Fits many electric bikes in the market like Razor, Baja, Schwinstingray, Sun-L, X-treme etc.