Hello, this is a good condition pre owned shirt. Armpit to armpit is  20 3/4 in, back middle under collar to bottom seam is 28 in.

Quiksilver lingo KTO means little boys ages 4-7
BTO is bigger boys ages 8-18
Mens/adult is MTO

Thanks for looking, I ship Mon Thru Fri so you get your items fast, please view my other listings and save with a combined shipping discount. I ship to your confirmed ship to address unless you contact me prior to shipment, thanks!