When trying to decide between two sizes, choose the larger size for a better fit.
SizeLengthChestNeckWeight on PackagingRealistic Weight Range
SM9.25"15"10"16-34 lbs5-15 lbs
MD14.5"18"12"35-55 lbs20-35lbs
LG17.5"23"14"56-75 lbs35-50 lbs
XL20"29"16"76-90 lbs55-70lbs