Reptile Systems Compact Pro Zone 3 12% 3U lamp is a professional designed and tested lamp. It is important to ensure that all reptiles, and amphibians are provided with the correct heating and lighting equipment for optimum health and development. The Reptile Systems Compact Pro Zone 3 3U lamp offers 12% UVB for the synthesis of vitamin D3, and 30% UVA which produces excellent natural colors whilst still only using 23 watts. Reptile Systems Compact Pro lamps have an electronic starter built in so you don’t need and more hardware. For best results replace every 6-9 months. This lamp is designed to be mounted horizontally.