With a 20-second latching LED, adjustable volume, tone and sensitivity, the Mamba 3+1 Alarm Set can be tailored to your preferences. The magneto-dynamic speaker with a digi amplifier ensures crystal-clear alerts. Crafted with a high-impact body and weatherproof double-sealed unit, it's built to withstand the elements. The set includes alarms, a receiver and a power out socket, all packed in a shockproof carry case. Plus, the low battery warning and manual power control keep you in control.20 second latching LED Adjustable volume Adjustable toneAdjustable sensitivity Magneto-dynamic speaker with digi amplifier High impact body Weatherproof double sealed unit Low battery warning Manual power on/off Power out socket Supplied in shockproof carrycase Alarms require 3X LR1 12v batteries Receiver requires 3X AAA batteries