The picture on the upper-left is a picture of an extension cord which I feel has been designed badly. I feel this way as the plugs for the 2-pin plugs are too close to each other, so sometimes when I fit a plug like the one in the picture, I cannot fit another beside it, leaving me no choice but to fit it on the plug further from the first plug. The picture on the lower-left shows what I mean. The solution is quite simple. The designer just needs to put a gap between each plug so that people will not need to waste 1 plug.