An ice maker apparatus is provided that may include a casing, an extruder die, an auger, a heat exchange body, and a fin portion. The casing may define a chamber about a central axis and extend along the central axis between a top portion and a bottom portion. The extruder die may be mounted to the casing at the top portion of the casing. The auger may be disposed within the chamber. The heat exchange body may be disposed in thermal engagement with the chamber. The heat exchange body may include a base wall extending along a portion of the casing and a sidewall extending outward from the base wall. The heat exchange body may also define an air duct across the base wall and sidewall. The fin portion may include a fin extending outward from the base wall. The fin may define a plurality of subchannels.