Fanuc A20B-9001-0780 AC spindle sensor. This type of spindle motor sensor is a optical pick up 12 pin feedback device sold with or without cable. Normally for speed, position for the CNC controlling early generation AC spindle motors. This number is the common reference number this sensor is known by. Regardless you’ll always get the complete sensor with pcb.
DNC offer used refurbished sensors with warranty on an exchange basis (assuming in stock). Testing, fault diagnosis, and outright sale (stock permitting) of the A20B90010780 sensor is possible.