Firestone Heavy-Duty Ride-Rite Air Helper Springs are the workhorse of the Air Helper Spring Line. The double convoluted air springs offer maximum load support as well as years of worry-free service. Ride-Rite Air Helper Springs can be installed on most light trucks, motorhomes, RVs, SUVs and vans. Ride-Rite Air Helper Springs are installed between the frame of the vehicle and the suspension, providing load support through the use of air pressure. Ride-Rite Air Helper Springs utilize a pair of convoluted air springs which can be adjusted for changing loads. These air springs are capable of 3, 200 to 5, 000 lbs. of load leveling capacity. Ride-Rite Air Helper Springs enhance the ride by reducing inter-leaf friction. Please remember that air springs do not increase the load-carrying capacity of your vehicle. NOTE: This is the replacement air spring bellows for Firestone Ride-Rite Kits F2299, F2330, F2398, F2400, F2450, F2451, F2528, F2535, F2550, F2560, and F2579.• Improves steering control and braking effectiveness• Levels headlight beams and reduces tire wear• Levels off-center roads• Individual inflation valves• Keeps leaf springs from permanent sagging• Softens contact between axle and frame• Increases vehicle stability and absorbs road shockSpecsType: Air Double BellowsExtended Height: 8.91"Compressed Height: 3"Diameter: 7.52"Load Capacity: 2, 500 lbs. Inflation Port Size: 3/4" NPT Replacement air spring bellows with 2500-lb. load capacity 3/4"" NPT inflation port size | Firestone 6401 Ride-Rite Replacement Air Helper Spring Bellows