The Bilstein B4 range are high quality gas shock absorbers that are engineered as direct replacements for the worn factory shocks on your 3 Series. Made in Germany by the very best in the industry, these shocks will vastly improve the way your BMW rides and handles due to their design and use of high quality componentry. The perfect solution for most people, they will restore the finesse and suspension damping back to the way your car felt when it first rolled out of the factory. These replacement B4 shock absorbers are designed for sedan and wagon models that have been optioned with M Sport suspension.