Bite Not Pet Collar BiteNot Collars are an excellent alternative to the traditional Elizabethan collar. It provides unimpeded peripheral vision and allows your pet to eat, drink, sleep, and play while protecting the back, rump, base of tail, flanks, chest, abdomen, and genitals (even feet in small breeds). These collars are not recommended for protecting eyes or ears. These collars are made of flexible plastic and foam and are machine-washable helping you easily keep it clean. They are the only cervical restraint with a harness strap, and that means these collars stay on. When choosing size, remember that the collar must stretch from behind the animal's ear to the top of its shoulder for maximum protection. Features: Provides unimpeded peripheral vision Excellent alternative to the traditional Elizabethan collar Protects back, rump, base of tail, flanks, chest, abdomen, and genitals (feet in small breeds) Cervical restraint with a harness strap Item Specifications: How to measure: While your dog is standing, measure from the base of the ear to the top of the shoulder blade. This measurement will give you the desired width and size of the collar. For example, if you measure 6", you will need a size 6. Dog Sizing: Size 3.5": for dogs under 10 lb. (i.e. toy poodle) Size 4": for dogs 10-17 lb. (i.e. Bichon, Shih Tzu) Size 5": for dogs 18-30 lb. (i.e. Spaniels, Terriers) Size 5L": for dogs 31-45 lb. (i.e. Chow, Pit Bull) Size 6": for dogs 46-70 lb. (i.e. Labrador, Golden Retriever) Size 7": for dogs 71-100 lb. (i.e. Rottweiler) Size 8": for dogs 101-140 lb. (i.e. Bullmastiff) Cat Sizing: Size 2.5": for cats under 10 lb. Size 3": for cats over 10 lb. Materials: Plastic, Foam Cleaning and Care: Machine-washable Warnings: Not recommended for protecting eyes or ears Recommended Use: When choosing size, the collar must stretch from behind the animal's ear to the top of its shoulder for maximum protection.