The first ever metal nocking loop. Provides the ultimate, even balanced, release point directly behind the arrow. Designed to be used with a shallow engagement release aid including caliper releases. Stops arrow from falling off string. Increases accuracy and consistency by improving arrow flight. Eliminates arrow pinching and bowstring wear. Unlike other metal nocking loops has four not two anti-vibration screws to keep the Ultra-Nock securely on your string without sliding, maintaining accuracy shot after shot.