The Impact Liner capitalizes on the positive qualities of a spray-in liner without all of the negative limitations. The Impact TPO material on the bed floor is bonded to a 100% polypropylene foam backing. The non-abrasive backing will not damage the finish of your truck bed. Its 3/4" of closed cell foam padding provides impact resistance not available with spray-in liners. This protects your truck bed, your cargo, and your knees when climbing in and out of the bed. The Impact Liners are designed for folks who work out of their trucks. From gravel and cinder blocks one day to antiques and camping equipment the next, the Impact Liner handles it all. The Impact Liner is made with material that is fade and UV resistant, impervious to chemicals such as bleach, diesel fuel and even battery acid, and it will not mold or mildew. You can buy Impact Liners with confidence because they carry a limited lifetime warranty against manufacturing defects.