10x12” should be good. So if you’re looking at the MEPC, get the medium. Most carriers it’ll end up being a medium for that size. You’ll never need a plate bigger then 10”x12”. You want the plates to be on the tighter end inside of the front/rear bags instead of on the looser end. So you don’t have extra fabric and a sloppy pc.9" even, nipple to nipple. A little over 16" notch to belly button.