Revshift polyurethane bushings completely replace the oem rubber bushings on all E36 cars except for the 318ti. These bushings stiffen the suspension improving the vehicles handling capabilities. - Improves handing- Will not wear out like oem bushings- Properly dampens suspension componentsThis kit includes:- Subframe bushings- Trailing arm bushings- Differential bushings with bolts- Front control arm bushings- Revshift bushing lube We offer a 14mm (2.0 thread pitch) bolt option for the front bushing. The OEM front bolt size is 12mm and it is the standard option. Drilling and tapping the differential housing for a 14mm bolt is a common upgrade. Please specify if you want the OEM bolt or the 14mm bolt. Lifetime Warranty Sold as a complete kit Hardness80A Street (Black): Slightly stiffer and stronger than OEM rubber. Minimal 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/polyurethanePlease specify the hardness, control arm bushing offset, and differential bolt size.