Product Code: STSECH401 Echo Anti Rocker Wheels STSECH401 | Graphite | 4-pack These anti-rockers are carefully shaped for the best possible performance. At 45mm x 24mm these grind rocks will fit most frames in the market and will require spacers and bearings to function. The grind rocks are made from hard urethane that is shaped to size. Replace inner wheels with these to help with grinding and sliding. Specifications: Dimensions: 45mm x 24mm Wheels: Sold in packs of 4 Hardness: 101A PU Cast Colour: Graphite