Feature: 1.For the dog with, avoid dog unintentional injuries to passers-by; 2.Effectively prevent dog picked wild unclean food; 3.The effective prevention of dog's barkin; 4. Soft and comfortable, the size can be adjusted. Size: S Mouth Circumference 12cm(4.3inch) Head circumference 12-27cm Suit for 2.5-4.5 kg dogs M Mouth Circumference 15cm(5.3inch) Head circumference 15-33cm Suit for 5-5.5 kg dogs L Mouth Circumference 16cm(6.4inch) Head circumference 16-35cm Suit for 9-12.5 kg dogs Package Included: 1*Dog Muzzle