The tail is straight and carried erect, but never curled or laying over the back. COAT Coat is short, and close-lying but hard, dense, and abundant. Coat should cover the belly and the inside of the thighs. Brindle, red, liver, or slaty blue. A balanced dog of these proportions should weigh about 18 pounds.
Bitches are normally slightly lower in height and lighter in weight, but with the same proportions.
GAIT A Smooth Fox Terrier moves with a brisk stride of moderate length. Coming and going, the forelegs and hind legs swing parallel to one another and perpendicular to the ground, like the pendulum of a clock. When moved on a loose lead at a moderate speed, the hocks and elbows are the same distance apart as the feet. Viewed from the side, the front legs extend well forward, but with very little height between foot and ground. The rear leg swinging forward contacts the ground at approximately mid-length of the body.