The Colombian weasel has a long body. It has an average length of 22 cm (8.7 in). Its tail is 11.5 cm (4.5 in) long. It weighs between 120 and 150 g (4.2 and 5.3 oz). The Colombian weasel has a dark dorsal color. It also has a light orange color. The bottom of the feet does not have any fur. It has webbed feet that is found on the second, third, and fourth toes.