SIZING

Size 1 - 19.5" PTP
Size 2 - 20.5" PTP
Size 3 - 21.5" PTP
Size 4 - 22.5" PTP
Size 5 - 23.5" PTP

*PTP is the measurement from one arm pit to the other.

If unsure on the fit, compare measurements to another item you have that fits.