size chart

SIZE WEIGHT ESTIMATE CHEST CLOTHES LENGTH
XXS 0 - 4 lb 9" - 12" 7"
XS 4 - 8 lb 12" - 15" 9"
S 8 - 15 lb 15" - 19" 12"
M 15 - 35 lb 19" - 24" 16"
L 35 - 65 lb 24" - 29" 20"
XL 65 - 120 lb 29" - 34" 24"

As seen in