Mouthpiece size-type/ligature question

[vi scose poise]

I am interested in purchasing a new ligature for my moutpiece (Kessler 50NY) and I have been asked to choose between Otto Link, Larsen or Dukoff sizes. I only understand that these are mouthpiece types.

What type/size is the Kessler 50NY?
Are there any online explanations of these sizes?

[newlifesax]

Toll Free: 1-888-385-4559
mailto:music@kesslermusic.com (music@kesslermusic.com)

I know it may seem overly obvious, but why not call or email Dave Kessler and ask this question. After all, it's his product. He also is all over this site.

BTW, I play one of his alto NYSS pieces and use a standard Rovner EV-1 lig on it.