night heat lamps of 15 watts. The Exo Terra Night Heat Lamp simulates natural moonlight to allow for nocturnal viewing without disturbing your pet reptiles day/night cycle. The emitted light is bluish due to the use of blue glass. The heat generated by the bulb is minimal but sufficient to provide tropical night temperatures. The lower wattage of these bulbs does not interfere with natural nighttime temperature drops. It can also be used to stimulate breeding behavior in reptiles and amphibians.