light bulbs as a UV source are weak, fragile and lose what little effectiveness they have over time. Flourecent sources are better (the cat spray version that Ross is showing is flourescent). I believe that what Von has is incandescent. I have both of these and find that the one Von has is really praticle in the casino to check out UV coding. It is what I used to use at the Luxor for their coded $1 chips.

The problem with Von's model is that if you carry it around, the on button is often depressed and when you go to use it the batteries are dead! I have seen similar cylendrical light sources (laser pointers) with a guard that prevents this from happening.

The best small unit I have used is one made to look like a beeper and be clipped to a belt. It uses a 1 inch long, 1/8" diameter flourescent tube and other than sub-par manufacturing, its a great little device. Operates on a single AA battery with a good switch button. (The typical manufacturing issue is soldering of the wire leads to the tube!)

Jim