American Percherons average 1,900 pounds (860 kg), and their top weight is around 2,600 pounds (1,200 kg).[2] In Great Britain, 16.2 hands (66 inches, 168 cm) is the shortest acceptable height for stallions and 16.1 hands (65 inches, 165 cm) for mares, while weights range from around 2,000–2,200 pounds (910–1,000 kg) for stallions and 1,800–2,000 pounds (820–910 kg) for mares.[3] They are generally gray or black in coloring, although the American registry also allows the registration of roan, bay and chestnut horses.[2] Only gray or black horses may be registered in France[1] and Britain.[3] Many horses have white markings on their heads and legs, but registries consider excessive white to be undesirable.