Ensure your desert reptile has proper UVB levels with the Exo Terra Desert UVB 150 Reptile Bulb. Reptiles require UVB light to absorb and metabolize calcium which is essential for healthy bone growth and preventing metabolic diseases. Exo Terra Desert UVB 150 Reptile Bulb has a very high UVB output similar to natural desert environments where there is more direct sunlight and more UV exposure. This bulb can also be used on screened terrariums or terrariums with dense screen covers to ensure UVB penetration.