Of course, everyone knows that laser-sealed borosilicate glass vials that are internally coated with phosphor will create a cold energy that produces a light source when injected with gaseous tritium. It's as plain as the nose on your face.
The manufacturers of our Glowrings, who produce military equipment and other need-to-see-at-night items, have taken this everyday nugget of basic science and made it their business.
A Glowring is small enough and tough enough to attach to anything you might need to use in the dark, a bunch of keys being the most obvious. But because they can glow for a few years, you can leave them hanging off things that only come out once in a while like fishing gear and camping equipment. It does have to be pretty dark to see the glow, but that's the point.
Glows in the dark!
Available in Blue, Red or green