So you are looking for an emergency light for your outdoor adventures? The UST See-Me 1.0 has you covered. It is a waterproof LED light that is visible from 3.4 miles in the dark. It offers 20 lumens of 360-degree light and runs up to 17 hours on 2 AAA batteries.
The See-Me 1.0 LED light has an IPX7 waterproof rating. It measures 4.95 x 1 inches. You can find out more here.