This is an E27 lampholder, also known as an Edison screw. It works with traditional incandescent bulbs, CFL bulbs and newer LED bulbs. E27 lampholders sometimes get stuck in a locked safety position and need to be unlocked before they can be installed. In order to unlock a Lampholder, locate the center terminal that goes to the edge of the bakelite socket.
Press down on the edge with a screwdriver. You may have to press a few times to get it to unlock. It is a matter of approximately 1 mm. You then twist the socket and unscrew it when the terminal has been pushed down sufficiently
With the socket taken apart, I strip the ends of the electric cable and screw it into the socket screws.
If you have a 3 wire cable with a ground wire, you would connect it to the screw located at the base of the socket
I disconnected the lampholder and threaded the wire through the lamp chassis. I then screw the lampholder to the lamp base. With the lampholder on the lamp base, I tie a relief knot in the electric wire which will keep the wire in place.
I then reconnect the wires to the socket screws. I screw in the lampholder and lock it in the secure position. I then add the lampshade
With the lampholder installed, I then proceed to attach an electric plug to the other end of the cable and an on off switch
With everything connected, I test to make sure that everything works as it should
