Desert reptile species in particular are naturally exposed to strong sunlight and require relatively high concentrations of UV-B light and so should be kept under a 12% UV-B D3+ Reptile Lamp. ¥For Desert Species ¥12% UVB for the synthesis of vitamin D3 ¥30% UVA ¥Produces excellent natural colours Arcadia Reptile D3 and D3+ T8 lamps have been specifically designed with the animals health in mind. We are proud to have the world's highest output T8 lamps in a true 6% and 12% UVB. All of our UVB percentages are measured as part of the total output of light from the lamp and AFTER the all important first 100 hours of output. You can be rest assured that by using Arcadia Reptile D3 and D3+ lamps that you are providing the very best in T8 technology that money can buy. The Arcadia Reptile D3 and D3+ UVB lamps are effective to for one whole year and will keep your animal in tip top condition.