10x15x4 ABEC-5 Ball Bearings Stainless Steel S6700ZZ Ceramic Balls Pack of 10 Hybrid Ceramic bearings S6700ZZ Stainless Steel Ball Bearings and ceramic balls ABEC-5 quality, S6700ZZ is a popular size that could be used in many application that uses this size 10mm x 15mm x 4mm. S6700ZZ Bearings are made of Stainless Steel, each S6700ZZ bearing has 2 metal shields to protect the bearing from dust or any possible contamination, S6700ZZ bearings are pre-lubricated with grease.