Feel safe while jogging, shopping, biking or any time you need the reassurance knowing help is a signal blast away. Sound 911 Personal Safety Horn sends out a 112-decibel blast of piercing sound to deter a would-be assailant or unfriendly animal. This convenient, compact device can be heard up to 1/2 mile away and attaches easily to your belt or wrist with the included Velcro® strap. The Sound 911 Personal Safety Horn is 100% safe for the ozone and requires no wires or batteries.