Sleep soundly at night safe in the knowledge that you will detect any unwanted entry into your house. This highly sensitive door lock has a built in siren that will emit an ear splitting warning alarm should any intruders attempt to force your door. Sets instantly so there is no need to fumble with chains, and has adjustable sensitivity.

• Compatible with both right and left hung doors
• Uses a E23A battery (supplied)

Source:  Expert Verdict

Popularity: 15% [?]