Threading a line through this tightener is easy. Simply pull on the release trigger located at the top to loosen the ball bearings, thread the end of the line through the center and hook the tightener's loop to your clothesline post. Voila Your clothesline will be up and ready in no time. To tighten, give the end of the clothesline a pull to loosen the ball bearings until the clothesline is taut. This tool will prevent your clothesline from slipping and keep your fresh linens off the ground. While best for clotheslines with pulley systems, this tightener can be used with fixed lines as well. Save yourself the time and energy of constant re-tying with the addition of this clothesline tightener to your laundry day routine.