Edam Spirit & Esprit solid axle adapter
Edam release a new optional part for the Spirit and Esprit 1/10 scale on-road cars in the form of this solid axle adapter. The insert turns the gear differential into a solid axle for those who prefer to use a front one way and a spool rear axle. Best suited for high-grip surfaces as the conversion provides stability, a more linear acceleration and also saves some weight over the stock gear differential.
Source: Edam [edamhoby.com]