Made with special UV transmitting quartz glass, the UVB and UVA emissions last approx 12 months and is flicker free. This 26watt bulb provides a full spectrum light replicating natural sunlight, providing all the known health benefits. Providing the correct levels of UVB allows birds to synthesise Vitamin D3 in their skin, or through a special process involving the preening gland. Vitamin D3 is essential for proper calcium metabolism. This is necessary for normal growth, maintenance of strong bones and egg production. Birds have specialised retinas that enable them to see UVA, helping them to recognise mates, locate food, and identify different species. Without UVA, birds are deprived of the full colour spectrum they see in nature and are colour blind. Unlock their world and let your bird see it in full colour! It should be used between 6 - 8 hours a day. UVA is essential for the psychological health of your bird. Using lighting that emits UVA can also help to curb feather picking and other destructive behaviours. Please note this bulb is not compatible with the Arcadia Lighting Reflector.