Day White Light Incandescent Spot Bulbs. Provides focused lighting and heat source ideal for reptile basking areas Simulates the natural daytime photo-environment of the reptile's habitat* The bulb simulates the natural photo-environment of a desert or tropical habitat while generating a heat source needed for a healthy reptile environment. Photons from the daylight spot bulb provides a focused beam of heat and light that pass through the glass heating the opposing surface, creating a direct basking spot for reptile. The bulb is made from glass containing rare earth neodymium phosphors produce a brighter, whiter light. This full-spectrum lamp emits energy across all visible wavelengths from 400nm to 700nm and UVA rays from 315nm to 400nm. *For UVB output, use Zilla Desert 50 and Tropical 25 UVB Fluorescent bulbs This Product/Package Measures: 4.00 in. L x4.00 in W x5.50 in D br/>Sold in Quantity of: 1