A large dark sunbird with a long and deeply curved bill. Both sexes show a large yellow panel in the wing and yellow sides to the tail. Males are mostly blackish, but in breeding plumage have copper iridescence on the breast, head, and back. Females are dark brown on the back and pale below with a yellow wash. Found in montane woodland, grassland, gardens, and forest edges.Easily separated from other sunbirds by the golden wing. The song is a high-pitched sizzle, and the most common call is a rattling “tr-tr-tr-tr-tr.”