4 functions, 2 in one switch. Big problem, instructions say attach 20 amp to 5 amp lite switch. wiring complicated, others commented on same, check internet for suggested work arounds. When I wired per instructions, only fan came on if light switch in certain position. Heater wouldn't come on any position. Also most manufacturers wire switch (white) through hot side, so bulk of run is only hot or active when on. Panasonic puts hot (white) on return like, so bulk of switch is hot all up to switch and return to switch. I wasn't taught that in school many years ago by my instructor. 'Common feed shunt' not explained, is that some kind of Panasonic protocol?
once installed with modified wiring, switch performs nicely.