I’ve been using one of the early versions of the Merkava I glowring (main photo) for 4.5 years and couldn’t be more comfortable recommending them as the best gift for anyone that operates in the dark. These little tritium glow sticks are waterproof, batteryless and glow brightly for 10-20 years. They clip to zippers, keychains, flashlight tailcaps, sleeping squadmates and anything else with a hole, loop or droopy appendage. Once attached, identifying and finding (or avoiding) the marked item is easy.
What are they and how do they work? I asked Merkava the same question. His reply: “Inside each glowring’s polycarbonate case is a 3mm x 23mm laser-sealed glass tube called a Gaseous Tritium Light Source. The inside of this tube is coated with phosphor. The electrons in the gaseous tritium excite the phosphor, causing it to glow continuously without any external power source.
When it comes to finding my keys, I need all the help I can get. I’m sorta minimalistic and my keyring is small and has just the bare minimum of things I think a keyring needs; keys, a ring, a biner, and a multitool, but one of the teeny ones.
I also just leave them on the first available flat surface I find, meaning I can never, ever remember where they were last.
I’ve thought about getting one of those beepy radio keyring finders, but they don’t hang well. In a pocket, I notice them too much. Frankly, anything larger than a key on a keyring bothers me.
But that’s all just a justification. I suddenly have a need for a glow-in-the-dark keyring that’s powered by the beta emissions cast off by tritium gas.
Beta radiation is for all intensive porpoises harmless. If you crack open the vial and huff it, or mechanically dilute the hydrogen isotope into some some water and drink it, well it might affect you. So don’t do that. Otherwise, skin is an excellent shield against that type of radiation.
Tritium has a half-life of 12 years, so it should stay visible for, oh, 18 years; if you’ve seen a watch that glows on its own, like the Luminox watches (designed for the SEALs, natch) then you’ve seen Tritium at work.
It’s also used to power night sights and optics. It has been thus harnessed and made it into keychains.
The four models are made to-order by a dude, Merkava, on the Candle Power Forum. He’s planning on getting a real, well, web storefront up soon. They’re apparently extremely durable and glow in the damn dark with their awesome radioactive super powers!
- Merkava I Glowring, shown below on my 4Sevens Quark 123 flashlight. These are the original silicone encased tritium tubes. This is the smallest glowring and comes in 8 colors.
- Merkava II Glowring The second smallest glowring, the II is a a thin, clear polycarbonate tube with a tritium vial inside.
- Merkava Clear Glowrings are thicker clear, uncolored polycarbonate bodies containing one of 8 colors of tritium vials.
- Merkava Nite Glowrings are identical to Clear Glowrings, except their outer casing is color-tinted with a similarly colored tritium
The cool factor is just too much. I’ll be getting one shortly.