A: K4 plAstic bAck 12V single relAy*12V*1A*40A* Air conditioner relAy
B: K4 plAstic bAck 24V single relAy*12V*1A*40A* Air conditioner relAy
C: K4 plAstic bAck 12V relAy with socket*12V*1A*40A* Air conditioner relAy
D: K4 plAstic bAck 24V relAy with socket*12V*1A*40A* Air conditioner relAy