ACL Race Main Bearings Mazda B1 B3 B5 Z5-DEDesigned to withstand high RPM temperatures and load these high strength bearings are manufactured by ACL from 3 layers of hardened steel copper and nickel. This "trimetal" composition substantially lowers friction and thus reduces the operating temperatures while providing superior lubrication.These bearings are sold in complete sets (for a complete engine).If you require non-standard grade bearings or HX references or are performing an engine rebuild feel free to contact us for a detailed quote - we stock many internal parts and can provide most required for complete engine repair.Compatibility models and engine codes : Mazda B1 B3 B5 Z5-DE - 1.1L 1.3L 1.5L