The body is slim and lengthy. The ends of the upper and lower jaws have between fifty and one hundred tactile hairs, with a characteristic cluster of hairs located at the point of the lower jaw. Dorsal and flank areas brighten to white, but ventral sections remain dark gray to brown. The tips of the narrow, pointed flippers are sharp. With a distinct median notch, the flukes are huge, narrow, pointed at the tips, and remarkably well-defined, almost exactly like those of the blue whale. The upper jaw has 350–360 baleen plates, each measuring 36 inches (90 cm) on average in length and ranging in hue from bluish-gray to white.