I have a quick question about interpreting a screw specification on a repair diagram. I am usually pretty good with buying replacement screws and threads/sizing but this screw is a metric size (which I am less familiar with) and is written in a way that makes me stumped.
The part description, exactly as it appears on the schematic, is: 'Screw M 4x10K'. Now, M4 is the nominal outer diameter of the head (in mm). Usually, the part following the 'x' is a length (in mm) but the 'K' part is confusing me. Is the 'K' an additional specification or class of screws or is '10K' some length-related specification itself? The screw goes through a plastic part and into a metal part on a vacuum. The manufacturer is based in the UK so I am having some difficulty sorting out what this could be.
Thank you!