Lamp base adapter

A lamp adapter comprising:

• a hollow lamp adapter having an open end;
• a threaded internal sleeve mounted inside the lamp adapter to receive a lamp having a base of a first type;
• an external sleeve mounted on the outside of the lamp adapter and having threads of a second type;
• and
• a flange extending axially from the open end,
• wherein the flange has a length to prevent a closed fixture rated lamp, when installed in the lamp adapter, from completely threading into the threaded internal sleeve and to enable an open fixture rated lamp, when installed in the lamp adapter, to completely thread into the threaded internal sleeve.

A lamp adapter for completing an electrical circuit with a class of lamps having a threaded external sleeve about a base member and a central metal button contact mounted on the base member comprising:

• a lamp adapter of insulating material having an open first end and a closed second end and a bore having a first section at the open first end and a second section at the closed second end;
• a metal sleeve in the second section;
• and
• internal threads on the metal sleeve to receive the threaded external sleeve about the base member of an inserted lamp from the class of lamps wherein the class of lamps comprises an open fixture rated lamp having a medium base,
• wherein the first section extends a length from the first section which allows the threaded external sleeve of only open fixture rated lamps having a medium base to be inserted therethrough and threaded into the metal sleeve in the second section.