Vacuum Advance Unit, correct for Lucas 25D, dist. no. 41491. Push on vacuum line connection. OE 54425359
Original manifold vacuum unit made special with OS diaphragm, Heavy Duty Diaphragm, much improved over other replacement advance units found on the market for this application. Manufactured as a heavy duty with the diaphragm locked into the pressed edge to prevent failure and manufactured in original appearance. USA made and stamped with OE number