Arnott's new product line for the rear of the BMW X5 includes a new rear air spring featuring a Continental ContiTech bladder assembled with the highest-quality materials and backed by Arnott's Limited Lifetime Warranty! This kit comes complete with rear air spring and seal. Arnott recommends replacing Air Springs in pairs. Vehicles equipped with the Sport Suspension from the factory have firmer, shorter springs resulting in a lowered vehicle stance, along with shock absorbers that have been valved to yield firmer dampening. If you are unsure if your BMW has Sport Suspension, contact your dealer with the VIN to verify.