PETCO Nylon & Mesh Dog MuzzleOur PETCO Nylon & Mesh Dog Muzzle inhibits dogs from biting, barking and chewing while still allowing your dog to drink, pant and vomit.This adjustable quick fit muzzle features strong, yet soft flexible breathable nylon mesh that fits your dog comfortably. Additionally, the well-built design makes it difficult for dogs to dislodge.Selecting the proper muzzle for your dog:Measure around the widest part of your dog"s nose using a tape measure.Place your finger between the measuring tape and dog"s nose to ensure enough space for breathing and drinking.Record the length of the measuring tape and select appropriate muzzle size.Muzzle Size ChartSizeNose MeasurementIdeal for:04-4.5"Toy Poodle, Yorkies, Miniature Dachshunds15-5.5"Dachshunds, Jack Russells, Westies, Whippets25.5-5.75"Beagles, Border Collies, Cocker Spaniels, Springers37-7.5"Bull Terriers, Dobermans, German Shepherds, Labs, Setters48.5-9"Danes, Wolfhounds, St. Bernards59.5-10"Bull Mastiffs, Large Boxers, Rottweilers.