Reese Fifth Wheel Rails (Bracket Kit Not Included)Reese Outboard Fifth Wheel Mounting Rails Only (10 Bolt Design) SAE J2638 COMPLIANT Based on heavy duty, accelerated life cycle criteria developed by SAE for fifth wheels J2638 are fatigue and static requirements based on the European style test of 900,000 cycles HARDWARE Grade 8 hardware, meets all Canadian requirements FAST CUSTOM MOUNT SYSTEM Rails are wider (48) for faster install , because the mounting points are outside the truck frame, allowing