This differential bushing will fit all BMW E30 models, E36 318ti, and Z3. Revshift bushing lube included. Lifetime warranty Hardness80A Street (Black): Slightly stiffer and stronger than OEM rubber. No increase in NVH. Great choice as an upgraded stock replacement (OEM+).95A Track (Green): Significantly stiffer and stronger than OEM rubber. Noticeable increase in NVH. Excellent for enthusiastically driven street 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.(NVH = noise, vibration, harmonics)Learn more about choosing polyurethane here: https://revshift.com/pages/polyurethane Please specify the hardness
