The most important feature of a fluorescent lamp is the ability to emit sufficient UVB light, a component of sunlight. The Exo Terra Reptile Glo 5.0 provides high levels of UVA (30%) and UVB (5%) making them suitable for reptiles that are seen in shady environments like rainforests. The vegetation and high humidity in these environments filters out or prevents direct sunlight from striking the animals and their basking sites.