As I said, I don't know offhand.
If I don't have it listed on the site, then measure the thickness of the flange and add the nominal diameter of the screw. If it falls "between quarters," (say, 2-1/16"UHL,) then get the next size
longer (2-1/4", in this case.)
The thumb rule for maximum strength of a screwed joint is 1-1.5
d in thread engagement (with
d being the nominal diameter.) For a bolted joint (mating internal and external threads on wrought fastener, vice wrought male thread into mating thread in part,) it's full engagement in the nut plus 1-2 threads (just for the sake of completeness.)
Likewise, if I happen to have a measured UHL (Under Head Length) "between quarters," get the next quarter
longer. If it's going into a blind hole, pick up some flat washers as well, you may need them to prevent the screw bottoming out in the hole.