Zoo Med's linear fluorescent 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. Emits UVB a full 20"/51cm from the surface of the lamp to prevent or reverse metabolic bone disease. (Compared to 12"/30cm on the ReptiSun 5.0.) Optimal for use with larger terrariums where greater than 12" of UVB penetration is needed. The ReptiSun 10.0 is also recommended for use above screen covers which can filter out up to 50% of the UVB wavelengths This is an offering for multi quantity bundle - 2 count