A damper mechanism (4) is provided with a first plate (21), a second plate (22), an output plate (33), a plurality of spring sets (49), a first spring seat (44), and a second spring seat (43). The output plate (33) comprises an annular body portion (33a) and a plate-shaped transmission portion (33e). The transmission portion (33e) comprises a first protrusion (33c) that extends radially outward from the body portion (33a) and a second protrusion (33b) that extends axially to the engine side from the end of the first protrusion (33c) in the circumferential direction.