This sleek, compact modern design keychain attaches to backpack, purse or keys for convenient, instant access, plus greater value with batteries included (requires 4xLR41). The 110 dB dual siren alarm helps call for assistance in an emergency and helps deter attacker (audible up to 600 feet/185M away). Simple to use and reusable; pull metal chain from device to sound 110 dB alarm; push pin back in to stop sound and use again. Safe for children, and a self-defense option for any age. Supports RAINN (the Rape, Abuse & Incest National Network).