Security Alarm Anti-Theft Luggage Finder

This is a new, unused item that has been stored for a long time.
All instructions are in English, so I don't know how to use it.
I am looking for buyers who can understand the English text in the photos and are aware that this may be a junk item due to its age.
Please refer to the photos for the contents.
The synthetic leather case is deteriorated.
Inside the synthetic leather case, not visible in the photos, are a Phillips head screwdriver, a chain clip, two AAA batteries, and a computer security lock.
The included button battery is new, but its expiration date has passed. It is unknown if it is usable.
Please determine how to use it from the English instruction manual.
I apologize. I wrote detector, but I don't know the specifics. I'm sorry for the inaccuracy.
It's quite old. I think I bought it to prevent theft because I often stayed overnight on chairs at overseas airports. In the end, I didn't understand it well and never used it.
Free shipping. Anonymous shipping.
Thank you for your cooperation with simple packaging.