Hellwig Lp-15 Medium Duty Rear Helper Springs are secondary leaf springs that reduce weight on OEM leaf springs and provide support for extra loads. Their load carrying capacity is up to 1500 lbs. They easily restore proper ride height when towing a boat or small trailer, keeping your ride steady and comfortable. Hellwig Lp-15 Medium Duty Rear Helper Springs reduce leaf spring wrap-up, bottoming out, and loss of cornering traction. They have a fully adjustable progressive spring rate.