The SOUND GRENADE+ is an ultra-compact personal alarm—small in size but big in sound. Once you pull the pin, the device emits a 130-decibel (ambulance-level) alarm. The siren will sound continuously for 30 minutes until the pin is returned to device. The SOUND GRENADE+ allows maximum utility for those intending to use it indoors or outdoors with a rugged rubber water-resistant shield. The extra bottom hook feature allows for easy construction of a tripwire or campsite alarm. Includes battery and metal carabiner.