The Zoo Med ReptiSun 10.0 UVB T8 Fluorescent Lamp emits essential UVB light up to 20 inches (51 cm) from the lamps surface, helping to prevent or treat metabolic bone disease in reptiles. This is a significant improvement over the ReptiSun 5.0, which only reaches 12 inches (30 cm). It is ideal for larger terrariums requiring deeper UVB penetration beyond 12 inches. Additionally, this lamp is perfect for setups with screen covers that may block up to 50% of UVB rays. Key Details: Offers 10% UVB and 30% UVA, crafted with superior quality in Germany.