Seeking UV Flashlight Recommendation

[MolaMola]

I have never used a little light I see tons of people have at frag swaps to get an idea of coral coloration.
Is it just UV LEDs and the wavelength doesn't matter much? In a quick online search I saw a crazy set covering a spectrum of wavelengths (also crazy expensive). What are hobbyists using?
Any recommendations of cheap ones? Students would use them to examine frags when we study waves or other physics/chem and in an ocean class. If I were super cool I could find out if we could make our own from LEDs and Harbor Freight flashlights. Hmmm.

 

[Enderturtle]

http://www.bareefers.org/forum/thre...ght-for-coral-fluorescence.17911/#post-261472

I like the alldaymall blue led lights. Its rechargable but you gotta buy a charger. See thread above.

I think the blue is what causes coral fluorescence.

 

[Ibn]

Picked up one of these and brought it to the swap:

https://www.amazon.com/gp/product/B00W5PCM90/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

$10 shipped (via Prime) and uses AA batteries. Seems to pop the fluorescence in the corals well enough from preliminary testing.

8/29 Edit. Quick and dirty test with the LED flashlight.