Tie Down Ends: Side rails feature built in tie downs for additional cargo securing needs.Optional Cross Rail Bars: Optional Tec Rail Cross Bar Rails available that still 9″ taller than the Tec side rails and side 13″ above your cargo box.Work & Sport: Great for Contractor with a Boss headache rack and the outdoor adventurer.Dual T-Slot Channel Bed Rails: All the rails and bars have double t-slot channels for mounting tons of rack accessories.