The Zilla Day Blue Light Incandescent Reptile Bulb provides the heat source necessary for reptiles to bask and keep their body temperature regulated. The day blue lamp is ideal for tropical and desert habitats and helps enhance your reptile’s coloring. This full-spectrum light emits UVA rays from 315 nm to 400 nm for a healthy reptile environment. The blue glass is uncoated， which allows the bulb to transfer more heat to the enclosure so you pet can bask in its warmth.