The Zilla Day White Light Incandescent Bulb simulates the natural daytime photo environment of a desert or tropical habitat while providing a heat source needed for a healthy reptile environment. Provides basking heat source for reptiles to regulate their body temperature Simulates the natural daytime photo environment of the reptiles habitat Great for desert and tropical reptiles Photons from the Day White Light Incandescent Bulb pass through the glass heating the opposing surface allowing the reptile to bask in its warmth. The Day White Light Incandescent Bulb is coated with rare earth neodymium phosphors to produce a brighter whiter light. The Day White Light Incandescent Bulb is a full spectrum lamp that emits energy across all visible wavelengths from 400nm to 700nm and UVA rays from 315nm to 400nm. The Day White Light Incandescent Bulb Provides basking heat source for reptiles to regulate their body temperature and simulates the natural daytime photo environment of the reptiles habitat.