More important is the size of the bolt that is used to go through the hole .
a 1- 7 /8" ball can be had with a 1 /2" bolt and 5 /8" and 3 /4"
a 2 " ball can be had with 5 /8" , 3 /4" and 1 inch.
It may be that all larger balls are 1 inch only .
In any event it might be obvious that the largest bolt size you can find is worth the effort because these balls last forever .
I have a fleet of stingers , each with its own dedicated ball , and one dates back to 1972 . I bought it for my first new car a 1972 C/20 Suburban with the 402 big block .
The rest have various drops and ball sizes .
i've never had a ball loosen .
I will put a little dab of grease on the ball head on occasion.
