Core made of High-Carbon AISI 52100 Chromium Alloy Steel features higher wear resistance, fatigue strength and steel hardness, Premium quality MolyPro™ NLGI Grade 2 Molybdenum Grease (MoS2) to minimize wear and reduce friction providing longer lasting performance, Exclusive multi-lip seals are made with ProSeal™ Nitrile Rubber (NBR) which can successfully function at high delta of temperatures while retaining its flexibility and sealing performance, Inner rings are made of Case-Hardened Steel for improved resistance to surface wear and contact fatigue, Thickness and metallurgy electronically validated for manufacturing consistency, SAE J1714, J2525 and J2535 validated for OEM load-carrying capacity, durability, and performance characteristics, Part Reference Numbers : 1410-44501 WE60368 91-44501 94-44501 S510060 NT510060 WH510060 391060 H510060 510060 FW60 TRB-510060, Part Reference Numbers : 1410-246634 WE60370 91-246634 94-246634 S511038 NT511038 WH511038 H511038 511038 GRW274 WB000002 TRB-511038, Kit Includes: 2x Front Wheel Bearing (Both Side) + 2x Rear Wheel Bearing (Both Side)