types of registers
Registers are located at the ends of the ducts and are fitted at the bottom of a wall, in a floor or near the ceiling.
Grill at the end of an air-return duct, which returns a room’s air to the furnace.
Grill at the end of a duct through which a room’s air is drawn to mix it with the forced hot air.
Adjustable grill located at the end of a duct through which hot air is distributed throughout a room.