It's not mean - it's a SOFTIE.
The softie Dog Muzzle is a temporary, reliable restraint, ideal for grooming, training and treating your dog. If dogs could talk, they'd ask for the Softie, because it is comfortable and allows them to pant and breathe. The Softie is made from patented Dupont fabric which is exceptionally resistant to abrasions, punctures and tears. This is an easy care, wash and wear product. Available in five sizes to fit most breeds.
The breed chart below is just a general guide. For correct fit measure your dogs snout circumference and add 1/2 inch for smaller dogs and 1 inch for bigger dogs.

Small
Circumference of the Small is 7-1/2"
For Minature Poodle, Bichon Frise, Minature Schnauzer, Shelties, Yorkies, Cavalier Spaniels & other Miniature Breeds with similar size snouts. This muzzle is Blue
Medium
Circumference of the Medium is 9-1/2"
For Small Beagles, Fox Terrier, Keeshound, Whippets, Westirs, Jack Russels, Standard Dachshunds, Standard Poodles, Lhasa Apso and dogs with similar size snouts. This muzzle is Orange
Large
Circumference of the Large is 11"
For Border Collie, Large Beagles, Springers, Cocker Spaniel, Fox Terrier and dogs with similar size snouts. This muzzle is Green
X-Large
Circumference of the X-large is 12-1/2"
For German Shepherds, Rottweilers, Labs, Golden Retrievers, Huskys, Doberman, Wolfhound, Setters and dogs with similar size snouts. This muzzle is Yellow.
Giant
Circumference of the Giant is 16"
For St. Bernard, Great Dane, Newfoundland, Bull Mastiffs, Great Pyreness and dogs with similar size snouts. This muzzle is Red
CAUTION:
Designed for midly aggressive dogs only. Practical usage recommended. Use only with direct supervision. Never leave your dog unattended. Using a muzzle for an extended period of time can interfere with your dog's natural cooling system.