Heavy-Duty 30mm Rear Bumper Keeper Kit for CIK Sprint KartsEver wondered how top racers stay unflappable when hardware stress tests hit? The secret often lies in smart backups like the BKK 30MM Rear Bumper Keeper Kit, optimized for 30mm frame rails in demanding CIK environments. This kit, sold as a pair, deploys robust aluminum clamps to anchor your rear bumper uprights. Should a bolt shear or loosen amid aggressive driving, these keepers step in, holding everything steady to dodge that dreaded black flag.