This is a guide (feeder) for the rug yarn cones or balls which helps you to provide a smooth and easy connection with your tufting gun while tufting.
You can place it on the top of the tufting rack.  It is compact and easy to assemble- disassemble, you can simply screw it on the top of your tufting rack or use a clamp (clamp is not included in this listing). The guide makes your tufting process much more comfortable allowing the yarn thread to go down through your gun smoothly and evenly.