REPTI ZOO UVB Tester Reptile Lamp UV Sensor Reptile UVA UVB Fluorescent Lamp Tester Card, Set of 2

The media could not be loaded. Works great, very easy to use. I have a bearded dragon and it helps to know if my UVB are still good.

Works great directly under bulb. Thanks

This is perfect. Ideal for its intended use--just hold it around your pet's enclosure to see if the UV light is reaching whatever spot you're testing. I found out that the UV light just... wasn't. I moved the light, and within a day or two my bearded dragon was much more active and happier.When you hold the card up to UV light--or wherever you're testing--there's a purple sun on the left side of the card that slowly appears (~10 seconds or so to full appearance) if the UV levels are sufficient, like transitioning glasses lenses. The sun fades away slowly (a minute or two). The drawback is that if you're testing multiple spots in the enclosure, you'll need to wait for it to fade to test again. But to mitigate that, the package includes two cards.I can't speak to the longevity of the card, but it claims that each is reusable up to about 500 10-second exposures. They're cheap enough that even if it doesn't quite last that long, they're easily replaceable.I had no bias either way ordering this, but I will never set up an enclosure again without one. It's that useful.

It changes color to show whether there is UVB. The purple is lighter or darker depending on where it's placed. It works within a few seconds.The picture against the wooden background is outside the terrarium so no uvb. The picture with very light purple on the rock is on one end of the terrarium so less uvb there. The picture with my bearded dragon is about 9" below the lamp that's sitting above the mesh cover of the terrarium. It's darker than the one on the rock suggesting there's more uvb there. The last about 2" below the lamp and it's the darkest purple.As others have said, it does not give the uv index but the varying colors gives a clue as to the intensity of uvb. It works for what it's designed to do.

Works well

I bought this to quickly test if my bearded dragon’s UVB light was still emitting UV. I found this card really easy to use. Like some people said, it doesn’t differentiate between UVB and other UV but it quickly turned purple and the bulb should still be good so I’m taking that as sign the bulb is still good.

This worked perfect for telling if my uvb was reaching my bearded dragon.

This profuct you hold under the light and it turns a shade of purple. It's really hard to tell "ok" vs "change soon", but you can see CHANGE NOW easily. It's just subjective because it's colors the card changes, not values or anything quantifiable, which I would prefer. Good for the price.