The Sun Ringle Envy Rear Rim provides top of the line performance through a double wall design and welded seams to create a stiff, fast, and durable BMX racing wheel. Features: Durable BMX wheel designed to take a beating Eyeletted spoke holes and a welded seam make for an impressively durable rim Specifications: Effective Rim Diameter (ERD): 390mm (20"), 492mm (24") Rim Walls: Double Wall Brake Type: Rim Brake Rim Joint: Welded Rim Dimensions: 22mm (Internal Width), 18mm (Height) Tire Type: Clincher Material: Aluminum Color: Black Weight: 405g (20"), 502g (24")