If you're going to make your own bows you need a tillering cord. This one is a full 76", 18 strand tillering cord with a nylon serving wrapped upper loop. The nylon wrapping protects the main body of the string from limb abrasion for a long cord life.
To use, simply slide the loop over your upper bow limb and tie a bowyers' knot (timber hitch) on the lower limb. Tillering cords are a must have for bow building.