

When rekeying double cylinder deadbolts, I usually add a second user key to the inside cylinder. That would be the ideal key that they leave in the lock or hang next to the door. The reason is if a house guest steals the key thinking they'll come back later as a burglar it will not work the outside locks, although the key for the outside (master key) will also work on the inside. This particular one I installed a thumb turn on the head of the key so it does not look like just a key left in a lock.