Ariat kids half chap size guide

Size	Width/Height
Small-Reg (SR)	9.5" / 11.5"
Small-Tall (ST)	9.5" / 13"
Medium-Reg (MR)	10.5" / 12.5"
Medium-Tall (MT)	10.5" / 14"
Large-Reg (LR)	11.5" / 13.5"