They are not SK ot similar, but do the job for the larger bike axle nuts. However, notice that the metric sockets are SAE 3/8-Inch Drive.
I also see a 1/2 drive metric 1/2 Drive Metric Socket Set (not deep though), : 12 Point, 10, 12, 13, 15, 17, 18, 19 & 22MM for $19.00. They are a dollar more at Amazon.
But you should be able to us e a 5/8 socket for 16mm, while 19mm is about 3/4 .
Hope this helps.
I generally bought Craftsman when I bought tools. They are almost as good as SK or Snapon, and so far as my usage goes, they are good enough. Invariably you could not get the 16mm or 18mm sockets or wrenches in any tool set you bought from Craftsman unless it was the super deluxe set.
They are not SK ot similar, but do the job for the larger bike axle nuts. However, notice that the metric sockets are SAE 3/8-Inch Drive.
That is true so far as I have found buying tools here in America. Metric tools here come with drive sizes of 1/4, 3/8,1/2 and 3/4. (and I suppose you can get 1" drive for them too.)
I wonder what ratchet drive sizes they use in Europe?
But you should be able to us e a 5/8 socket for 16mm, while 19mm is about 3/4 .
That has never worked for me. They often just round off the bolt or nut i'm trying to remove. Oddly enough, even though 16 and 18 mm are usually absent in various tool sets i've bought over the years, they are invariably used in many vehicles I have worked on.