A shortened adapter for a light bulb socket with highly overlapped male and female parts with an insulating hand-ring that extends only partially over the external surface of the adapter's female threading so it fits into the unthreaded collar of a light bulb socket, thereby significantly reducing the light bulb displacement. The shortened adapter can respond to an incoming signal and control the output of a light bulb. A reversible ring on the insulating hand-ring can change the adapter from being a dimmer to being an on-off control. A mechanism is disclosed to reversibly lock the adapter onto a light bulb. A miniature remote controller to work with the adapter is provided that has many advantages because of its very small size and compact shape. Further, one such controller can control several lights and several such controllers can control a single light in arbitrary combinations selected by the user.