Characteristics
Powerful, stocky, athletic, imposing. Distinctive head with forbidding expression.

Temperament
Natural guarding instincts, vigilant and courageous without aggression. A good companion and very affectionate.

Head and Skull
Large with characteristic expression and appearance. The skull is broad, wider at ears than eyes. The upper region of the skull is slightly rounded from side to side. Pronounced stop forming a near right angle with the muzzle. Distinct median groove, lessens towards the back of the skull. The forehead is a prominent feature of the face but does not overhang it. The head is slightly furrowed with fine symmetrical wrinkles on each side of the median groove, but without excess. These are mobile when the dog is alert. Prominent cheeks due to very strong muscle development. The muzzle is powerful, short and slightly hollowed below the eyes with moderate folds, the width hardly decreasing towards the tip of the muzzle, when viewed from above looks square. Topline of muzzle is slightly turned up. Length from nose to stop between a quarter and one third of the length of the head. Broad, well-opened nostrils, well pigmented according to mask colour. Jaws very powerful and broad. Lower jaw curves upwards. The chin is well defined and must not overlap the upper flew excessively nor be covered by it. Upper flew thick, moderately pendulous in profile and shows a rounded lower line. In front, the edge of the upper lip meets with the lower lip then drops on each side, forming an inverted wide 'v'.

Eyes
Oval, set wide apart. Frank expression. Showing no haw. Colour hazel to dark brown for dog with black mask, lighter colour tolerated in dogs with brown mask or no mask.

Ears
Relatively small, of slightly darker colour than coat. The front of the base of the ear is slightly raised. They must fall forward and down but not hang limply, the front edge being close to the cheek when the dog is alert. The tip of the ear is slightly rounded, not reaching beyond the eye. Set rather high, at the level of the upper line of the skull, appearing to accentuate its width even more.

Mouth
Undershot, the back of the lower incisors not in contact with the front of the upper incisors. Strong teeth, particularly the canines. Lower canines set wide apart and slightly curved. Incisors of good size, well aligned, especially in the lower jaw where they form an apparently straight line. Teeth not visible when mouth closed.

Neck
Strong, muscular and solid, skin supple and loose. Circumference almost equals that of head. The well defined dewlap starts at the level of the throat forming folds down to the forechest without exaggeration. Neck very broad at base merging smoothly into the shoulders.

Forequarters
Well laid shoulders, withers well defined. The legs are strong, exceptionally muscled and as straight as is compatible with a broad-chested dog. Pasterns strong and slightly sloping.

Body
Chest broad, powerful and deep, let down below the elbows. The depth of the chest is slightly more than half of the height of the dog at the withers. Ribs well sprung, but not barrel shaped. Back solid, broad and muscular. Topline as straight as possible and maintained while on the move. The length of the body is greater than the height at the withers as 11 is to 10 measured from the point of the shoulder to the point of the buttock. Underline slightly tucked up.

Hindquarters
Broad loin. Rather short and solid croup moderately sloping down to the root of the tail. Hind legs strong and muscular. Well angulated stifles. Well-developed second thigh. Low set hocks.

Feet
Strong. Toes tight. Nails strong and curved. Pads well developed and supple. Well up on his toes despite his weight. Hind feet slightly longer than front feet.

Tail
Very thick at the base. Tip preferably reaching the hock. Carried low. Raised when the dog is in action, but never curving over the back or curled. Kinked tail highly undesirable.

Gait / Movement
Movement is free, quite supple for his size and weight and close to the ground. Good drive from hindquarters, good extension of the forelegs. At a faster gait, the head is carried lower. Absolute soundness essential.

Coat
Fine, short and soft to the touch. The skin is thick and loose fitting, without excessive wrinkles. Folds on the ribs or limbs highly undesirable.

Colour
Self-coloured, in all shades of fawn, from mahogany to Isabella. Chocolate highly undesirable. Good pigmentation is desirable. Limited white patches are permissible on the chest and the extremities of the limbs. White patches on the head or body highly undesirable.

Three mask colours allowed:

Black mask - mask must not extend above the eyes. Slight black shading allowed on ears, skull, neck and down the topline. Nose black.

Brown mask - nose and eye rims are brown
No mask - coat is fawn, skin appears red, nose may be reddish.

Size
Ideal height at the shoulder: Males (23½ - 26¾ ins); Females (22¾ - 26 ins). Weight: Male at least (110 lbs); Females at least (99 lbs).

Faults
Any departure from the foregoing points should be considered a fault and the seriousness with which the fault be regarded should be in exact proportion to its degree and its effect upon the health and welfare of the dog.