My favorite personal safety alarm is as loud as a jackhammer, and it just got an upgrade

A safety alarm may not be on everyone's radar, but as a 20-something woman who's traveled alone in and out of the busiest metropolitan areas in the nation, it's a must -- and it's for anyone of any age. 

I carried the She's Birdie personal alarm throughout college, and have continued to do so since. While I hope to never have to use it, every dollar I spent on it is worth it for the peace of mind it brings me. When the top pin of the Birdie is pulled out, a 130db siren sounds and a strobe light flashes for up to 40 minutes. To put that in perspective, a 130db sound is equivalent to a jackhammer and nearly equal to the sound of a jet engine in the distance, according to the Hearing Health Foundation. 

Also: This tiny keychain is a ...