This Model # DOF1855 is for 2018-2021 "Classic" Ram trucks with 5'7" beds (Does NOT work with RAM BOX, does NOT with with New Body Bed). Due to the mid-year change in 2019 this bedliner only fits select models for 2019-2021. This liner fits all full sized RAM models. This bedliner WILL NOT fit the "New Body Bed" models. This model is NOT compatible with the 2019 - 2021 Ram "New Body" 5'7" truck bed. New Type Of Bed Liner that combines all the best Bed liner features into one Bed liner system!The side walls are made from one of the toughest materials ever made, they are polyethylene exact fit panels that follow the exact contour of your truck. Near the bottom of the sidewall there has been a channel designed to house the Zero Skid Bed mat, this Bed mat is one of the thickest on the market, a full 3/8ths of an inch thick. This is several times thicker than most of the spray on's. The Zero Skid mat keeps your cargo in place which protects the cargo as well as the trucks box. Advances in manufacturing allow cleats to be added to the underside of the mat, this keeps the mat from laying flat on the trucks finish, while at the same time allowing water to drain out of the factory designed drain holes. Precise manufacturing allows each piece to be created to be the exact size and shape of your specific year, make, and model of truck.