Energy saving lights or LED light bulb will use E27 lampbase.TheE27 lampbase's material is nickel-plated ironnickel-platedaluminum or nickel-plated copper.Our company also haveE26/E14/B22lampbase.This is E27/27 Solder free/ Weld free lamp base. The color ofplastic part can be white, green, or yellow.This is E27/27 Solder free/ Weld free lamp base.It is our new item for LED bulbs or CFL bulbs.The color of plastic part can be white, green, or yellow.