Chain locks are not meant to be used as the main lock in your house. However, they still perform excellently in terms of reinforcing your main lock. Chain locks depend on the primary locking assembly on the door, as well as a catch on the door frame, to secure the door. It performs a similar function to that of a barrel bolt. However, instead of a cylinder part, a chain is used to achieve the locking function. The advantage of chain locks is that they allow you to see who is on the other side of the door. It is possible to do so without having to open the door entirely. It also doesn’t allow enough room for the individual to enter.
Alternatively, you may utilize bars instead of a chain. This additional lock may be installed with simplicity by a reputable home locksmith such as the Bar locksmith.