Core made of High-Carbon AISI 52100 Chromium Alloy Steel features higher wear resistance, fatigue strength and steel hardness, TQ OE-matched material gives our spring kit the ideal balance between tensile and hardness and provide consistent wear, long life, and quiet operation, Premium quality MolyPro™ NLGI Grade 2 Molybdenum Grease (MoS2) to minimize wear and reduce friction providing longer lasting performance, Independently tested with Noise/Vibration/Harshness (NVH) and durability/wear testing; resulting in high quality and reliable products, 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, Maintains proper movement for safe, effective stopping performance, Inner rings are made of Case-Hardened Steel for improved resistance to surface wear and contact fatigue, Kit Includes: 2x Rear Kugel Wheel Bearing and Hub Assembly (Both Side) + 1x Rear Top Quality Drum Brake Hardware Kit, Kit Variations: K7D-100231 K7D-100394 K7D-100778 K7D-100847