This is a Brand new Truck Bed Mounting Rail system that I Purchased from Ballard Inc. It's used to mount in your bed rail pockets to attach different mounts for equipment on. It's brand new never used and paid $200 for it! It comes 8ft long and can be cut down to any bed length! If you have any questions message me!
Link to the item:
https://www.ballard-inc.com/product/truck-bed-rail-system/