Thread holder I’ve labeled my vinyl with the vanilla tags that have the metal wires on one end. Just stab it through a corner and twist the wires. That way the tag sticks out the end of the wrack. Use to just tape them on with masking tape but left a residue or the tape came off. But sometimes I wish I didn’t have a hole in the material as I needed the roll to the end. I guess I should have clarified as to more what are your labeling techniques.