Brass E27 lamp holder, plain smooth sided supplied with cord grip and internal ES bulb socket.
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Brass Sleeved Cylinder Lamp Holder, E27 Lamp Fitment, 60W Max rating, CE Certified
As this item is double insulated a 2 core cable is only needed.
Edison lamp holders lock together as a design feature. The picture below is the showing the tab which has to be depressed and held down before the holder can then be undone.