SuperSprings K-30-007 SumoSprings Fits 10-24 ProMaster 3500 Sprinter 3500Air Helper Spring SumoSprings SumoSprings; Front and Rear; SSF 106 40 & SSR 338 48; SPECIFICATIONS: Max Load: 1400 lbs. FEATURES: Kits Contain Both Front And Rear Sumosprings Sold As A Pair Maintenance Free Enhances Load Carrying Ability 500 Lb Front And 1400 Lb Rear Capacity At 50% Compression Reduces And Stabilizes Sway Improves Overall Driver Control And Ride Comfort Compress Up To 80% Of Original Height With Full Memory Rebound One Piece Unit