The Exo Terra UVB 150 (formerly Repti Glo 10.0) emits very high levels of UVB similar to sunlight suitable for desert habitats, or reptiles naturally found basking in full sunlight. The UVB150 CFL bulb is also available in 26 watts, which emits more light and UVB to your pet rather than being blocked by screen tops. Most screen tops will block up to 50% of total light output.
UVB lamps should be replaced every 6 months when used 10-12 hours on a daily basis. This light will continue to emit light, but UVB output will diminish after 6 months.