Our ABEC-3 bearings use the same high quality steels as our ABEC-5 bearings. We use Grade 10 chrome steel balls in combination with R-62 hardened 52100 low carbon races made of high quality carbon. The ball catcher is riveted steel for extra strength. The LLB double lip seals keep out harmful contaminants and dirt. ABEC-3 bearings combine extreme durability and smoothness at an affordable price Dimensions: 15x21x4 - SC: 99