I'm so confused!

[thejinxii]

 I want to buy this cheap little harness for my fat mini, but I'm not sure if I should buy him the mini size, or the pony size. He is 36" tall, so pretty much the cut off for mini's, and he's realllllly big around. But nose to butt he's the same as any other mini...Help meeee

Here's the harness 
http://www.horse.com/item/tough-1-basic-nylon-driving-harness/BOT74/