2192000052 The Hitch Mounted OSL Attachment can be mounted to any 2 inch receiver hitch or 1-1/4 receiver hitch with optional reducer (sold separately). The unit has extendable corner flag mounting tubes that adjust to most vehicle widths and then lock into place with 3/8 inch bolts. The corner flag holders are removable and will accommodate flags with 5/8 inch dowels. The Hitch Mounted OSL unit comes with attachment points to mount any BTI OSL Sign with the BACK RACK brackets. This unit can be used on the front and rear of your vehicle provided you have a receiver hitch tube. (see front view photo in the photo gallery and rear view photo in photo gallery).