A fluid flow control valve uses a servo valve to control the pressure in a main diaphragm chamber defined by a main diaphragm. Unlike conventional remote controls which are moved from place to place, these miniature remote controls are so small they may be removably mounted at each location needed, unobtrusively or even hidden. The lock core rod includes a wedging part and an inner barrel disposed at opposite ends. The illumination module has a back wall, wherein the illumination module is removably coupled to the chassis module so that the illumination module back wall is spaced apart from the chassis module back wall.