Zoo Med ReptiSun 5.0 UVB Replacement BulbZoo Med ReptiSun 5. 0 UVB Bulbs provide the exact band of rays within the UVB spectrum for maximum vitamin D3 synthesis and calcium absorption. These low heat bulbs also emit UVA, which helps increase your reptiles appetite, activity and breeding. Simulates sunlight for maximum Vitamin D3 synthesis and calcium absorption Helps turtles and tortoises develop strong, healthy shells Increases reptile appetite, activity and breeding ReptiSun 5. 0 UVB Bulbs