When you unplug them, they have a habit of lying prongs upward. Standing on one naked Lego feel like a shag carpet. and to be honest the fuse isn’t really necessary with modern wiring f type plugs don’t have fuses in them and I’ve never had a problem with wires melting or anything. and with older sockets, the little flap that blocks the earth hole tends to get stuck. Apart from that they are the best.