The Mini Adapters fit both the regular-sized ChiaoGoo tightening keys and the Mini tightening keys. You'll need 2 keys to tighten the adapter onto a cable. Screw the adapter onto the cable with your fingers as tight as you can first. Then, place a key into the hole on the adapter and another key into the hole on the cable. Use the keys to turn the adapter and the cable in opposite directions. They shouldn't visibly move. After using the tightening keys you should not be able to unscrew the adapter from the cable with your fingers.