AKA stadium truck closed cell inserts
AKA introduce their famous closed cell inserts for the 1/10th stadium truck class. The insert was designed to decrease the lateral deflection of the tire while at the same time increasing the vertical impact absorption therefore providing better handling in the bumps. Lateral grooves allow the insert to flex vertically to absorb the large impacts while still maintaining lateral stability and overall durability. The inserts are usable in the front and the rear.
Source: AKA [raceaka.com]