The Super Reptile Linear UV bulbs have a higher output and divide the energy more recently over wider vivariums/terrariums. These bulbs are available in 4 wattages – 15w, 18w, 30w and 36w. They are also available in a choice of 3 UVB outputs - 2.0 UVB, 5.0 UVB and 10.0 UVB. Please select the bulb wattage and UVB output from the drop down menu when ordering. The 15w bulbs measure 45cm (18 inch), the 18w bulbs measure 60cm (24 inch), the 30w bulbs measure 90cm (36 inch) and the 36w bulbs measure 120cm (48 inch). 2.0 UVB Output Bulbs The Super Reptile Repti Linear Nebula 2.0 is a general light source with a high visual light output and a very high colour rendering index (CRI), but a lower UVB radiation. This bulb is suitable for snakes, all amphibians (frogs, toads and salamanders) and nocturnal animals. Plants will thrive under this light as well. It is also a perfect complementary light to a UVB bulb to boost visual light. 5.0 UVB Output Bulbs The Super Reptile Repti Linear Nebula 5.0 has a moderate to high UVB output, similar to that of shady environments such as rain forests and other tropical locations. Reptiles living in these habitats receive less UV radiation because of the many climatological conditions (fairly high humidity, changes in weather, etc) that prevent direct sunlight from reaching them or their basking sites. 10.0 UVB Output Bulbs The Super Reptile Repti Linear Nebula 10.0 has a very high UVB output similar to that associated with desert environments. Desert locations receive more direct sunlight than any other because of fewer clouds, less air humidity and no plants or trees to provide shade. Therefore desert reptiles are more exposed to UV radiation than any other type of reptile. This bulb can also be used on screened terrariums or terrariums with dense screen covers to ensure UVB penetration. Dense screens can filter out up to 50% of the UVB rays.The Super Reptile Repti Linear Nebula 10.0 has a very high UVB output similar to that associated with desert environments. Desert locations receive more direct sunlight than any other because of fewer clouds, less air humidity and no plants or trees to provide shade. Therefore desert reptiles are more exposed to UV radiation than any other type of reptile. The Super Reptile Repti Linear Nebula 5.0 has a moderate to high UVB output, similar to that of shady environments such as rain forests and other tropical locations. Reptiles living in these habitats receive less UV radiation because of the many climatological conditions (fairly high humidity, changes in weather, etc) that prevent direct sunlight from reaching them or their basking sites. The Super Reptile Repti Linear Nebula 2.0 is a general light source with a high visual light output and a very high colour rendering index (CRI), but a lower UVB radiation. This bulb is suitable for snakes, all amphibians (frogs, toads and salamanders) and nocturnal animals. The 15w bulbs measure 45cm (18 inch), the 18w bulbs measure 60cm (24 inch), the 30w bulbs measure 90cm (36 inch) and the 36w bulbs measure 120cm (48 inch). The Super Reptile Linear UV bulbs have a higher output and divide the energy more recently over wider vivariums/terrariums. These bulbs are available in 4 wattages – 15w, 18w, 30w and 36w. They are also available in a choice of 3 UVB outputs - 2.0 UVB, 5.0 UVB and 10.0 UVB. Please select the bulb wattage and UVB output from the drop down menu when ordering.