Bear tells me my stock string on my super mag is 16 strands of fast flight. No mention of the serving diameter.

I want to order some stuff including brass nock sets. What color/size do I need for this string? Kustom King has medium and large, and medium seems to fall in the right string count but I don't know if they're taking the serving size into account?

Also, is this type/size of string ok on a short bow like the supermag, or should I consider something else, and if yes, what?