Are you an archery coach or someone who likes to go out for target practice, but you don't want to keep a pocket full of spare nocks? This nock holder is sized for the Genesis 1820 N nock. You can easily attach this to a lanyard or keychain ring. It has a place in the back for three 8X3 mm magnets and a spot for the curve of an adjustment wrench to slide into place. Now you can have a spare nock and your adjustment wrench with you, and you don't have to wonder which pocket you put them in or where you sat them down. This design is not scalable.