The key ring is hung from the outside to bags and backpacks. He works like a grenade: pulled out a check and got a siren for 100 dB. The offenders will, of course, frighten and attract the attention of passers-by.
Personal alarms are used not only to protect a person. It can serve as an ornament for the bag. The keyring can be presented as a gift to close people. The gadget is very light and convenient. You can carry it with you all the time.
As soon as the owner of the keychain feels a threat from others, he can pull on the key chain, thereby sending an alarm. To read more detailed info, you can look into personal panic alarm. It will necessarily be heard by people who are ready to provide the necessary assistance. The key ring is particularly suitable for socially vulnerable groups: children, the elderly, and the disabled. Personal alarms can be used by athletes and people who regularly return to the dark streets with a night shift.