★Mass dampers help keep your car close to the track through sections where it can potentially jump. ★The block mass damper in this set can be attached in various places including front and rear bumpers. ★Small parts for attachment are included. ★Approximate weight: 14.9g. Compatible Cars MA and AR chassis cars; MS, FM-A, VS, Super-II, Super X, Super XX and Super TZ-X chassis cars using Item 15430. Some bodies may require modifications.