Core made of High-Carbon AISI 52100 Chromium Alloy Steel features higher wear resistance, fatigue strength and steel hardness, Engineered with Heat-Flowed cast iron to give our wheel cylinders the ideal balance between tensile strength and hardness, Premium quality MolyPro™ NLGI Grade 2 Molybdenum Grease (MoS2) to minimize wear and reduce friction providing longer lasting performance, Anodized coating provides complete 360º protection against rust, moisture and oxidation, 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, Reinforced pistons (FeSi) feature higher tolerance to pressure and increased wear resistance, Inner rings are made of Case-Hardened Steel for improved resistance to surface wear and contact fatigue, PCRVi (Pressure Conscious Reducing Valve integrated) reduces pressure buildup, Kit Includes: 2x Rear Kugel Wheel Bearing and Hub Assembly (Both Side) + 2x Rear Kingstar Drum Brake Wheel Cylinder (Both Side)