The flippers are pointed and have a distinct 'elbow' in the middle, and the dorsal fin , although much smaller than that of the killer whales, is still prominent and is distinctly hooked with a rounded tip.
There are 8 to 11 pairs of robust teeth in each jaw.
Most specimens are completely black but some may have a blaze of grey in the shape of an anchor from the tip of the lower jaw along the throat towards the navel and on the underside of the flippers.