The PPS23BLK is a special edition black version of our popular PPS23 series. For this special limited edition unit, in addition to the color, we"ve replaced the standard neck lanyard with a keyring and a bag clip. We believe this unit is the ULTIMATE personal alarm for purses, backpacks, and car keys. The PPS23BLK is a dual function emergency attack alarm. It features a 130 dB alarm, which is the loudest personal alarm sold by Vigilant. It is also the only alarm sold by Vigilant to include a backup feature - it has a security screamer whistle built into the end of the alarm that serves as an emergency backup alert mechanism in the event of battery failure.The alarm is activated by depressing the button on the front of the alarm, but a different button on the back of the unit is the only way to deactivate and silence the alarm. In situations where seconds make a difference between life and death - the ease of activation combined with the "hidden" off button make this alarm an easy to use, and hard to defeat personal alarm.Personal alarms are one of the fastest growing segments at retail in the self defense industry, because an attacker"s worst enemy is attention. Personal alarms are legal to carry in all 50 states (even on airplanes!) and are a very safe method of self defense. They require no training or skill to operate, and can be used by anyone regardless of age or physical ability. Victims are often too traumatized to shout for help in unfamiliar and dangerous situations, increasing their vulnerability. Criminals do not like to draw attention, and will likely run off when they realize the alarm cannot be stopped.The PPS23BLK is particularly suitable for teenagers, parents, night owls, delivery route employees, business owners, and college students. Joggers, walkers, and bicycle riders may enjoy the backpack/purse clip for hands free carrying.© Vigilant Personal Protection Systems by Vigilant PPS. Inc.