Prestige muzzles are ideal because they have no leather straps and the wire caging will not be a scratching hazard to your dog. It fits snugly around their head and can be adjusted to ensure it isn't too tight. 

Sizing:
(Small)
Front Width: 4cm
Front Height: 10cm
Back Width: 7.5cm
Back Height: 11.5cm
Top Length: 8cm
Bottom Length: 10cm

Fits dogs like Staffordshire Terriers and Small Cattledogs.