Team Bomber AK12 HQ ball diff
This HQ ball diff from Team Bomber is for their AK12 1/12th scale chassis and is specific to low traction asphalt. Replacing the kit standard solid shaft, it helps to give the car more stability even in unstable traction, keeping the rear of the car planted in the corners as well as under hard acceleration.
Source: Team Bomber [teambomber.jp]