To attach a parallel bar to a drafting table, you’ll need to get a piece of nylon twine. Attach one end to the bottom left hook on the table and through the bottom left runner on the parallel bar. Continue the line through the bottom right runner to the top-right hook on the table. Keep running the line through the top left hook, and cross the twine to the bottom left runner. Pull the line across the parallel bar to the bottom right runner and through the top-right hook. Pull the line to make sure it has enough tension, and tie it to the bottom right hook. You also want to make sure the bladed doesn’t slip in any vertical direction before you tie it down.