These are carbon fiber chassis stiffeners for use on the Tamiya TC-01 chassis. The parts expand your chassis flex tuning options. They are ideal to use when driving on high-grip surfaces and also ideal when looking to achieve sharper driving feel. Compatible Chassis: TC-01 Chassis - This 2.5mm thickness carbon fiber component connects chassis and front cover (K1) for a more rigid front of the car and exacting suspension, plus minimal drive loss.