Introducing the 5th wheel industry's first SAE J2638 Compliant rail kits, a fatigue and static requirement based on the European style test of 900, 000 cycles. These rails were designed and built specifically for the Reese R16 & R20 fifth wheel hitches, but are also designed to accept other models of Reese fifth wheels as well as most models from Draw-Tite, Pro Series, Hidden Hitch, Husky and Valley. These heavy duty cross rails are wider (48 inch) and install faster because the mounting points of the frame brackets are located on the outside of the truck's frame, allowing the installer to avoid under-bed components. All grade 8 mounting hardware is included.