This device is a type of fastener which allows several cables and/or wires to be bound together into a cable tree (the most common use). Due to its versatility, however, it can basically be used to securely tie anything together and keep them tied up (they've even been used as handcuffs)! Once the pointed tip of the cable tie has been pulled through the case and past the ratchet, it is prevented from being pulled back; the resulting loop may only be pulled tighter.