Grand Brass Lamp Parts, LLCStaff Answer
Jul 15, 2026 - 06:14 AM
Thank you for your question. Typically, yes. The listed diameter generally includes the cardboard insulating sleeve that comes installed on the socket.
The reason is that manufacturers typically measure the outside dimensions of the product as it is supplied and intended to be installed. Since the cardboard insulation is a permanent part of the assembled socket, it is included in the overall diameter rather than measuring just the metal shell underneath.
Please note that minor variations can occur due to normal manufacturing tolerances, but you can generally expect the published diameter to reflect the socket with the insulation in place.
