Boss Bearing DG4074-7 Rear Wheel Bearing Polaris Ranger RZR S 800 Kit is the aftermarket replacement for Polaris part # 3585502. Kit Contains: 1 Bearing This replaces one rear bearing. If you need to replace both rear bearings, please order 2. All Bearings feature low-drag double lip rubber seals on both sides. Double sealed bearings outperform metal shielded bearings because they keep out dirt and water.