Invisible Ink Pen with Ink Revealing Blue LED (4*AG3)

Pros: - Works perfect!
- Battery Included
- Very light
I tried over a lot of surfaces and it was invisible all the time (some issues with plastic and glass).

Cons: - The ink can be seen with a toy that my sister owns!
- Looks like the ink is getting yellow by now.
- If you are expecting permanent ink, forget it!

Other: For this price, it's a very entertainment toy! I recommend it!
I'm about to buy a few more to make a gift to some of my cheater friends! Looks like they are having problems hiding phone number! :)

Pros: it works just like it says it does really impresive especially to young children for this price i haven't found anything similar to my country

Cons: it didn't came in the picture's package but that wasn't really a problem this one is not really a con - i think the ink may not last for a long time but i'm not so sure yet

Other: it's really cool and usefull (i think) you can buy it for yourself or as a present either way you can't but like it

Pros: A fun wee pen, I bought one for my brother-in-law and he loves it, the ink appears to be water based so doesnt write well on plastic but its fine on paper card or skin. The UV LED works well to illuminate the ink

Cons: The ink is faintly visible enabling it to be read, some colours of paper make it less visible than others

Other: A fun wee toy for a young spy! Much fun has been had trying to keep messages secret from prying brothers

Pros: - Writes on many surfaces, including skin and wood! - I wrote on my door three days ago and it's still there, even though a little less bright. - Comes with it's own battery!

Cons: I had to remove the foil from inside the flashlight so it would work but mine still needed some messing around to get it to work, but it was easy enough to solve.

Other: If your first thought when you saw it was "cool!", buy it!

Pros: It is clear to see, when using it with the given lantern. Others mean of lightining are useless. Used it in my biology and math tests. Just great. an write in your whole body, and, yet, invisible.

Cons: The writtings appears in night clubs lightinings, when using it in the body. The ink is somewhat icchy, when applied in your skin.

Other: Great for fun, and cheating on tests. Unfortunately, you get more and more addicted to its use.