Hopefully you'll only use the Arva Evo4 Beacon for practice, but its intuitive design makes for fast and easy use in emergency situations. The Evo4 is Arva's least expensive beacon with three antennas, and Arva upgraded it with a clearer, digital LCD screen for this season. It can indicate multiple buried victims, and you can mark each victim while you scan each area. The Evo4 also features group check to make sure it's working with all the other beacons in your party. Arva's clip for safe function turns the Evo4 on when you clip it to the included holster. Arva also included the batteries, and they last 250 hours for long lasting use.