Push in connectors, could have been done by the assembler, or by the user in installing the cable into the push holes. Those do really need a bigger label on the embossing to say L and N on the base for correct assembly. I do not like them though they are very common , as the plastic ages and goes brittle with time and temperature, and then the contacts either fall out or arc. You really need to use a solid or 7 strand wire with them as well, the finer wires in cord tend to spread out on insertion unless you use a bootlace ferrule to hold them.
Funny thing is i recently bought some adaptors for SA standard 16A outlets to 2 pin Euro sockets like on cellular phones. The new ones come with a taped manual on them that says "Read Before Use". the older ones are subject to a recall because they are death traps and either cause shocks, fires or fail outright. I must remember to go around and see if any are still around and confiscate them, then return for new one, or just toss them. Hardest thing to keep around, they disappear overnight and when you ask "Ungaas".