The biOrb Intelligent LED allows you to create a 24 hour lighting cycle as nature intended - reducing the stress on your fish. Compatible with biOrb Life, biOrb Flow and biOrb Classic. Notcompatible with biOrb halo or Baby biOrb, Simply plug it in - no set up required. Sunrise, daylight, sunset and moonlight cycles, change at the push of a button with 7 different cycles to choose from. Automatic 24 hour timer just plug the light in and it cycles at the same time everyday. No need to change a bulb lasts 50,000 hours using long life, low energy cost saving LED\'s. Safe, low voltage, 12 volt power. Simple and quick replacement for the existing halogen light unit. Concealed in the aquarium lid and only 18 mm thick.