A lightweight muzzle and allows the dog to pant, drink and take treat. A great choice for off-lead running and activities such as canicross, bikejor and lure coursing.

Size 3- length 19.5cm / circumference 31cm
Size 4- length 21.5cm / circumference 31cm 

Length:
Measure the length of your dogs head in a straight line from behind their ear, to the tip of the nose. The muzzles are available 19.5 and 21.5cm long and also come with an adjustable leather strap. 

For dogs that measure 18-21cm you need the 19.5cm muzzle, for dogs that measure 21cm and longer you need the 21.5cm muzzle.

Depth:
This is important to make sure your dog can pant freely.
The circumference of each muzzle size is measured at the end of the basket where the dogs nose will be  and are available in 26, 31 and 35cm.
Hold a loop of tape at 26cm, 31cm, or 35 cm over the end of the dogs nose to see which size they will need to have enough room to pant.