Vigilant 130 dB Wearable Personal Protection Alarm with Backup Whistle and Neck Lanyard (PPS-23BL Black) 130dB PERSONAL ALARM: Creates attention in emergency situations LIGHTWEIGHT & COMFORTABLE: Weighing less than 1 oz, you won't notice wearing it all day RUGGED DESIGN: This personal alarm won't break in your most adverse conditions, it'll be ready to activate when you need it most BACKUP WHISTLE : There's a built-in whistle in the event of battery failure BATTERIES INCLUDED: 2X replaceable LR44 batteries are included, ready to use immediately