Features: brand new and high quality Made of high quality metal, durable and wear-resistant. Easy to install and meet your demand of RC car DIY. Conductive to assemble a powerful car.Reduce unnecessary shaking and ensure a stable driving. Transfer pressure flexible, no dispensable absent space produce.It can extend the wheel distance. Distinguished Sizes Wheel Hex Are Available.for 1/10 RC Crawler; Axial SCX10 TRX4 D90 RC Car Specifications: Material:Aluminum Color:Silver Type:12mm/15mm/18mm/21mm/6mm/9mm Size:6mm/0.24inches; 9mm/0.35inches; 12mm/0.47inches; 15mm/0.59inches; 18mm/0.71inches; 21mm/0.83inches Package Includes: 4 Pieces 1/10 RC Wheel Hex Hubs Adapters/Set note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.