Bones Swiss Ceramics Bearings are a high quality skate bearing manufactured using Bones Skate Rated design and high grade materials to achieve a high level of performance and durability. Bones Bearings are known around the world for speed and reliability. "The standard by which all other bearings are measured" *Skate Rated - Bones Bearings component parts are engineered and tested to withstand the high impacts of hard landings, the high side loads of turning, and (to the extent possible) the dirt of skate environments. Details: Kit contains: 16 pre-lubed bearings Single, non-contact, removable rubber shield for easy cleaning and less friction. Pre-lubricated with Speed Cream racing lubricant. High speed nylon ball retainer for greater strength and speed. Skate Rated clearances, tolerances, materials and lubricant provide the best performance and durability possible. Bones sticker Cleaning Instructions