Each Tube is operation-tested and built for long life and high luminous efficacy. 【UVA + UVB Output】 Available in 5.0 and 10.0 UVB options. 【5.0 /10.0 Options】 Choose 5.0 for many tropical/rainforest species needing lower UVB, or 10.0 for many arid species that require higher UVB.