Every vehicle on the road has a suspension system that's main job is to ensure your vehicle 's tires stay in constant contact with the road. The reason this function is so important is because if the suspension system isn't doing its job, many other systems such as steering and braking can be affected and worsen the quality of your ride. Both Shocks and Struts can improve your suspension. The biggest difference between Shocks and Struts is that a Shock is just an individual component of the entire suspension system while a Strut is actually a critical part of the chassis in addition to being a component of the suspension system. Belltech Shocks are manufactured with a 15mm piston rod, 35mm piston and a 55mm shock body. Teflon coated bushings and piston seals are designed to minimize metal on metal contact. Belltech Struts were designed to have balance between overall performance and comfort for your everyday commute by focusing on low speed compression and rebound characteristics. Whether you are upgrading your vehicle 's shocks or struts, Belltech Shocks / Struts will give you that performance boost you are looking for!