If you've ever tried to build a rubber band-powered car using, you'll know that the wheels are the most challenging and crucial material. Plastic bottle caps are too small, and CDs are difficult to attach to an axel. These large project wheels are designed specifically for educators, parents, and makers who want to build vehicles that work the way you expect. The 4.75" wheel diameter helps your projects go the distance, and the included rubber bands improve traction so no energy is wasted due to low-friction contact with the ground. We include 10 dowels made to fit onto the wheels, but please note: all types of wood craft require some manufacturing tolerance, so if your dowels seem a little loose, just wrap a layer or two of masking tape around the end for a snug fit. Questions or comments? Contact the seller! We hope this product empowers your creations.