The Yeah Racing Traxxas TRX-4 Brass Upgrade Parts Set is an all in one brass upgrade kit that includes brass portal covers (TRX4-019 - 42g), brass c-hubs (TRX4-040 - 49g), brass knuckles (TRX4-031 - 59g) and brass wheel adapters (TRX4-037 - 27g) for a total of 177 grams of added unsprung weight! This kit includes all the hardware needed for installation.