The Safeman is a lock you can keep in your pocket. Ideal for emergencies or for travelling, you just pull the cable ut from its drum and poke it in one of the holes to lock. Pull it tighter and it stays tight. Use the key to unlock and roll it up and put it back in your pocket or bag. Although not as secure as a chain or D-lock, its the perfect lightweight lock for travelling or for leaving in your bag for those moments when you have forgotten your proper lock.