Revshift Polyurethane Differential Bushings completely replace the OEM rubber bushings on BMW F8X M2/M3/M4. This bushing kit stiffens the differential mounting points improving the vehicles handling capabilities. These bushings are a two piece design which securely holds the differential in place preventing it from sliding or twisting. Features Improves handing Will not wear out like OEM bushings Properly dampens the differential Prevents differential from moving/twisting Includes new class 10.9 bolts Revshift bushing lube included Lifetime warranty Hardness 80A Street (Black): Slightly stiffer and stronger than OEM rubber. No additional NVH. Great choice as an upgraded stock replacement (OEM+). 95A Track (Green): Significantly stiffer and stronger than OEM rubber. Minor increase in NVH. Excellent for enthusiastically driven street cars and track cars. 75D Drift (Teal): Drastically stiffer and stronger than OEM rubber. Moderate increase in NVH. Most commonly used on dedicated drift and track cars. Vehicles SupportedBMW F8X M2 CompetitionBMW F8X M3/M4, including Competition