... balls. zinc-plated, nickle- plated, chrom-plated, copper cover Model Number2mm-50mmApplicationtoy, anit-rust purposeShapeshperialMaterialsteelDimensions2mm-50mmChemical ... , chrome plated and copper balls with size from 2mm to 25.4mm tude machines, hardware, bearings, wheel, ... bicyclesand trust bearing pulleys Copper Plated Ball/zinc-plated, nickle- ...