It's an electric winch where the main structural frame (or "body") is constructed from aluminum, and the drum is mounted horizontally—meaning the drum rotates around a horizontal axis, and the cable spools off the end of the drum.
This contrasts with the more common "vertical" or "Upright" winch design where the drum rotates around a horizontal axis but is mounted between two vertical side plates (like a traditional winch on a truck bumper).