Improve your acceleration. Only 4g per bearing. Being small in size, the 167 bearing offers the highest acceleration of any bearing on the market. Exactly what you need in Derby. It is also the lightest bearing on the market which also helps with acceleration. The bearing has double shields to stop dirt getting in and the bearings fits 7mm axles. Upgrade your bearings to the new 167 bearing from Bont. Patent Pending.