Zoo Med Daylight Blue Reptile Bulb is made of actual blue glass for superior heat transfer. A daytime heat source option that provides necessary UVA rays for ensuring a stress-free reptile and amphibian and can also encourage daytime activity in diurnal pets. Vibrant, long-lasting output enhances your pets coloring for ultimate beauty and pop! Utilize this heat lamp to provide a day/night heat cycle to make sure your pet's temp is always attended to. Use a lower watt bulb for increasing temperatures 5-10 degrees (measured 4" beneath lamp). High watt options are best used for providing a hot basking site for tortoises, turtles, bearded dragons, chameleons and more! This bulb does not emit UVB light.