1. This number of hex wideners is having a total width of 23mm to obtain a wider wheel distance for stabilization. 2. This few hex wideners is having 4mm opening that may be suited to countless other models provided the sizes are fit. 3. you will find o-ring utilizing one component and springtime steel musical business, springtime with washers, stainless screw in regards to the reverse aspect of tense up the hex wideners from free and a geniune delrin collar devote to secure the hex constantly in position so the tires and tires will not spin around, specially through crawling track your particular Axial SCX-10 II can face sufficient traction. Them includes :