Sizing Chart

SIZE Chest inches (A)
Neck inches (B) Weight
Small 12 - 21 12 - 18 6 - 25 lbs.
Medium 15 - 24 16 - 24 20 - 55 lbs.
Large 18 - 33 18 - 28 45 - 85 lbs.
X-Large 23 - 40 24 - 32 60 - 120 lbs.