The adult measures 34 to 45 cm, weighs from 265 to 560 g and a wingspan of 8 to 10 dm. As with most raptors, the female is slightly larger than the male. The adult has dark brown color and eventually black and white bands in tail. There are lighter forms that are confused with Buteo lineatus, but that species has more lines in bars, and in wings. It has relatively short, wide wings.