In the past few years, we have covered plenty of compact self defense tools here. This Self-Defense Keychain Set is also worth a look. It comes with a self-defense key, emergency whistle, no-touch door opener, and a security alarm.
The emergency alarm helps you be heard from 500ft away. The whistle has a noise rating of 110dB. You get a total of 10 items in each pack.
[where to get it]