Review on Maxxima Electrical Outlet Adapter - Enhancing Standard Outlets for Improved Compatibility by Gary Stringfield

This does exactly what it claims to do, adds sockets to a socket by plugging it into a socket. Pull the chain to turn the lights on and off while leaving the outlets active (assuming the light switch is on when the outlet is at the switch). I used them to plug into two outlets in my garage so I could hook up three LED shop lights. Works perfectly. Plug each LED bulb into an outlet and the bulbs are now on the switch. Leave a lightbulb in one of the sockets for the light to turn on immediately as it takes about 2 seconds for the LED bulbs to turn on. A simple product that does what it says on the tin at a good price.