IN A CLASS OF THEIR OWN If you want the best there is, this is it. The Bones Swiss Ceramics Bearings (8 pack) feature Cerbec ceramic balls that are much lighter, stronger, waterproof, and longer lasting than the finest steel balls. Features: Accelerate faster. Roll faster and farther. Resist dirt and moisture better. Help to repair injuries to your races caused by dirt. 1 non-contact, removable rubber shields allow easy cleaning. High speed nylon ball retainer for greater strength and speed. Skate Rated™ clearances, tolerances, materials and lubricant provide the best performance and durability possible.