Solarmeter Carolina Custom Cages Reptile Model 6.2 UVB Meter and Reptile Digital IR Surface Thermometer & Red Dot Pointer with Batteries Solartech's Solarmeter Model 6.2 UVB Meter has become the benchmark for measuring the UVB necessary to the health and well being of most reptiles. The only way for you to objectively judge the validity of claims by various manufacturers of UVB lamps and tubes is to be able to measure for yourself in your reptile's habitat. These outputs degrade very differently by manufacturer and type of lamp or tube, so again the only way to tell for yourself is to be able to measure in your reptile's habitat over time. Also, from a value perspective, if you can measure the lamp or tube that you decide to use over time, you can be sure that you put in a new one when it is time. No more potential wasting of a couple of months useful life "just to be on the safe side". In complicated habitats, being able to measure becomes a necessity for your reptile's health.