Zilla Tropical 25 UVB Fluorescent T8 BulbZilla Tropical 25 UVB Fluorescent T8 Bulb delivers extra UVB light essential for strong bones. Color corrected visible light brightens reptile colors. Designed to fit most fluorescent light fixtures. Recreate the healthy light of the tropical rainforest. Standard terrarium bulbs can't deliver the heightened levels of UVB radiation native to a tropical habitat, leaving rainforest reptiles deficient in a vital component of healthy bone development. Zilla Tropical 25 UVB Fluorescent T8 Bulbs correct this deficiency with a full dosage of UVB (25 microwatts per second/cm2) along with essential UVA light. Full-spectrum visible light output helps bring out subtle colors in a reptile's skin that makes everyday viewing more dramatic.17 Watt: is ideal for snakes, aquatic turtles, green iguanas, chameleons, frogs, toads, chinese water dragons, green and bahama anoles, newts and salamanders, day gecko, tokay gecko, crested gecko, leaf-tail gecko.15 Watt: is ideal for anoles, day geckos, tokay geckos, iguanas, basilisks, chameleons, tegus, chinese water dragons, red eared sliders, red foot tortoises, eastern box turtles.