The Koni Special Active Shock BMW 3 Series (E90) RWD Left Front is a special suspension shock designed to fit the rear-wheel drive BMW 3 Series (E90). It is made with a unique, patented active technology that allows for adjustable damping rates, allowing for a more comfortable and sporty ride. It also features an extra-long stroke for increased wheel travel and improved handling. The shock is designed to reduce body roll and improve stability, while also providing improved steering response and handling.