The URE Clamp Attachment is designed to clamp the 8' on various bars up to 2.75" wide. Use to mount to roof racks, trailer bars or other items. The URE Clamp Attachment DOES NOT come with hardware due to the wide range of possibilities to mount this item to. You will need to purchase the 3/8 - 16" bolts that will work in your application. You must utilize a lock washer with your bolts.