Nite glow keyring - illuminates for ten years - green colour

I've got the green as it seems to be the brightest; Great for finding your keys in the bottom of your bag. My mum's eyesight is not what it was and I've bought her one too. We've also got one on the loo light cord - so kids and visitors can find the pull cord at night. Not cheap but worth it.

These little glow rings are brilliant. I have had some for nearly 10 years, and they really do last that long. The green one is by far the brightest. Great for finding your keys in the dark depths of your bag, or anywhere else. Just turn out the lights and they will glow at you!

As a child I used to collect keyrings - yes, it was a bit of a rubbish hobby - but I enjoyed it, and had a fine (albeit tacky) collection consisting of all shapes and sizes. Nowadays, I don't get especially excited at the prospect of things to put on my keys - but I must admit to a slightly increased heartbeat when I saw the Nite Glow Keyring, a small hexagonal plastic vessel (4.8 x 1cm) containing a minute amount of radioactive material. The radiation makes said keyring constantly emit light - no batteries or sunlight required. Now you're probably thinking that a radioactive keyring isn't safe, but the packaging states that it most certainly is - personally, I've been taught not to believe everything that I read, and I plan not to place the keyring anywhere near my intimate areas...

So how does it work? well, the keyring contains Tritium, a radioactive isotope of hydrogen which has a half-life of twelve years. As the Tritium degrades, it emits electrons which can be seen as light - hey presto - a glowing keyring! The Tritium is housed in a laser-sealed polycarbonate vial which has been designated 'unbreakable' (thank God!) - however, I'm not going to test it by hitting it with hammer, or running it over with the car... radiation poisoning isn't something I want in exchange for a thorough review.

The keyring's light should last for over ten years, which is especially impressive considering the fact that it needs no external power source to function. I should point out straightaway that the light is very dim, and in normal daylight you wouldn't even know it was glowing at all. However, in a pichblack room its radioactive light is plain for all to see, and is visible up to thirty feet away. The keyrings are available in three different colours - blue, green, and pink.

The Keyring is especially good for putting on your keys, making them easy to find in the result of a power failure - similarly, i've heard stories of night fishermen tying them to the end of their lines, although personally, I'm not putting anything radioactive near my rod...

The metal loop for attaching your keys is nice and large, and the product is water resistant up to thirty metres. In terms of its weight, the keyring isn't at all heavy, and can easily be carried round without weighing down your pockets or bag. All in all then, if you fancy an extremely cool and maintenance free novelty keyring, then this keyring may be right up your street.