MVB is mercury vapour bulb - they are screw in style reflector spot bulbs that provide light, heat and UV in one. The more common ones are the Zoomed Powersun and the T-Rex Activeheat ranges.
They come in 100, 160 and 250W flavours, spot and flood, and the higher power ones can project UV as far as 6 feet. They are great for larger enclosures and pump out lots more UV than fluorescent tubes.
The downside is they are $40-50 each, and are very easy to blow if you knock them when they are on. They usually come with a one year warranty though.
Go to www.LLLreptile.com to check them out
www.LLLreptile.com
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Ross
0.2 Bearded Dragons (1 Yellow, 1 Chris Allen/Sandfire)