Here is the ampacity (maximum amount of current) that each size of this silicon wire can handle. Keep in mind that this is just a rule of thumb as ambient temperature and air flow will make a difference.
As it only seams to affect the price on the 18AWG and not the others, this was intended for HK. More as a comment then a question. I believe that somehow is a HK's pricing error. Either way doesn't matter and I don't really care. Again it was just a comment, after all this is the discussion section.
Quite small but still bigger than ordinary wire with the same size (18AWG) , nothing odd, the color is obviously RED, but because of it's silicone insulation plus small diameter, this cable is really very flexible, but also because of it this cable is very fragile to any sharp edges, be carefull.