That document is a little vague, it really does not state clearly that that 10 and 15 are Cat 1 and the 20 is Cat 2 and the 30 is Cat 3... Or so it would seem.... I guess that is what we get for documents written by engineers.... All it really talks about is the pins....
Dale
They have all the info on their site. Here's a link to the dimensions: https://www.landpride.com/ari/attach/lp/public/specs/320-003s.pdf