... I just recently purchased 15 of these lights from you. You advertise that they can be seen from up to 3 miles away. Well, after using them in a training exercise, I can tell you that they can be seen from over 20 miles away. This was in early morning conditions with ground fog. I was the scanner in an aircraft that was doing the searching, and had no idea where these beacons were placed. Yet, I found the 2 that were set up in a wooded area within 30 minutes of the search.
As I am a person that deals in air-to-ground search and rescue looking for lost hunters, hikers and missing aircraft, I can not stress the importance of this emergency device. Although it is meant to be used at night, in daylight conditions it still works very well. And if you are stranded, anything you can do to be spotted is a major help for the teams looking for you. This is an item that will save your life and well worth the little money it costs! 

From eBay buyer ridingelohssa