The 122 decibel ear-piercing shriek is louder than an ambulance siren, easily heard over most natural and man-made noises, so powerful that we ask you to use caution when using around others. Coming in at mere .4 ounces, 2.3 inches long, and with its flat surface, the JetScream fits comfortably in your pocket or anywhere you might need to tuck it away. The pea-less design and waterproof impact-resistant ABS plastic make the JetScream ideal for any and all weather conditions. No outdoor enthusiast would leave home without a whistle and the JetScream from UST is one of the most powerful signaling devices of its kind.