Mogul Base Porcelain Socket Extenders are intended for use in an existing mogul base socket where the light bulb socket needs to be extended to accept your desired light bulb or for aesthetic reasons. These E39 mogul base socket extensions are rated for 1500 watts and 600 volts. These socket extenders are to be used in porcelain sockets only. These socket adapters are 4KV pulse rated for HID only. This is a Leviton 8647-100 porcelain extension mogul to mogul. Please note: These adapters are UL and CSA listed and are a convenience item. Under no circumstances is it recommended to use multiple socket adapters in a single socket application.