Purchasing the correct size is critical for your pet to receive the best fit and protection to heal. The two measurements you will need is the collar measurement and the measurement from snout to neck. The collar needs to come past the nose of your dog or cat otherwise they might be able to reach one of their many body parts and delay the healing process.
The best way to make sure that your pet can not pull the collar off is to thread their collar or if your pet doesn't wear a collar simply thread a strip of gauze thru the elastic loops of the neck end of the “Comfy Cone” - this will secure the cone in place. With the Comfy cone your pet will feel like they are in their own little space which will help them maintain calmness, feel relaxed and heal faster.
SMALL Neck size: 8-10 inches or 12.5 cm
Neck to Snout: 5 ¾ inches
Breeds that might wear this size: Cats, Dogs Under 15 lbs., Maltese, etc.
MEDIUM Neck Size: 12-15 inches or 20cm
Neck to Snout: 8 ¼ inches
Breeds that might wear this size: French Bulldog, Cocker, Beagle, etc.
LARGE Neck size: 14-22 inches or 25cm
Neck to Snout: 10 ¼ inches
Breeds that might wear this size: Boxer, Dalmation, Aust. Shepherd
X-LARGE Neck Size: 21-25 inches or 30cm
Neck to Snout: 12 inches
Breeds that might wear this size: Golden Retriever, Rottie, German Shepherd, etc.