16 inline Skate Bearing Bronze Cage Openinline Skate Bearings BRONZE Cage 16 Bearings 16 skate bearings are Deep Groove Oil Preserved Radial Ball Bearings with BRONZE cage, The Bronze material is one of the least friction and less friction means higher speeds. Made from high strength chrome steel for durability and performance, also bearings are pre lubricated with Oil. 608 Ball Bearings Deep groove ball bearings Closures: Open Cage: Bronze (Less friction = Higher Speeds) Lubrication: Oil