I just received my laser comb (a Lux 9 model) and it came with the comb, the charging base and the power cord, but either I'm really dumb or there's a part missing because it appears to be impossible to plug in.

Here's a picture of the end of the cord which is supposed to plug into a wall outlet.


It looks like there's some kind of attachment that's supposed to go there, but nothing else was included in the case. What am I supposed to do with this?