Zoo Med's linear flurescent UVB lamps are made in Germany with the highest quality UVB transmitting quartz glass, with beneficial UVB emissions lasting a full twelve months!  The UVB emissions from these lamps will help to prevent or reverse metabolic bone disease in captive reptiles, birds, and other animals.  In addition to UVB, Zoo Med's ReptiSun , Iguana Light, and PowerSun lamps also emit beneficial UVA wavelengths which stimulate feeding, reproduction, and natural behavior patterns in reptiles, amphibians, and birds.  The award winning industry standard UVB lamp for reptiles.  A full 5% UVB output allows vitamin D3 synthesis to occur naturally, preventing or reversing MBD and other health problems in turtles and tortoises, bearded dragons, iguanas, and all other diurnal reptiles.  The ReptiSun 5.0 is effective for UVB induced photoconversion of D-3 in reptiles' skin at distances up to 12".  Accept no substitutes; get the original reptile UVB lamp Zoo Med's ReptiSun 5.0.