1About the base: E27, also available in E26,E11,E14,Mr16,Gu10 2Features: 1) Dimmable and non-dimmable are all available. 2)No heat, UV or infrared in the beam 3)No mercury, instant start, reduce co2 4)CE,RoHS,UL,TUV,ETL certificate 5)Cover Materials: high quality Aluminum 6)Light source: Edison, Cree or others can be made as per customers' requirements.