Hellwig Lp-25 Load Pro Series Rear Helper Springs are secondary leaf springs that work with OEM leaf springs and support extra loads. It is made for heavy hauling, work-truck use, or pulling 5th-wheel RV trailers. To install on full-size pick-up trucks and vans it requires mounting hardware (where applicable) to accommodate 2.53 or 33 wide OEM leaf springs. For ?half-ton? vehicles, choose Hellwig Lp-25 Load Pro Series Rear Helper Springs because their load carrying capacity is up to 2500 lbs. They prevent leaf spring from distortion due to continuous load compression. They manage proper rear ride height. When you are towing, Hellwig Lp-25 Load Pro Series Rear Helper Springs reduces bouncing at the rear side of your vehicle.