The plek'kak was a species of nerf-like animal native to the Sa'ari homeworld of T'lessia. Quadrupedal, they were approximately one meter high at the shoulder and two to three meters in length. They were characterized by their stubby horns, cloven hooves and thick, woolly coats that ranged in color from light gray to burnt umber. Unlike the Sa'ari, the plek'kak possessed two genders; the male was generally smaller with horns that were sharper, while the female was larger and bearing a thicker, woolier coat.