This is the 'blue' (shaft) rotary encoder used in Agilent / Keysight Infiniium series oscilloscopes, which usually have the smaller knob and finer clicks for dialing offset and trigger levels. Only the encoder itself is included. The PCB is on the picture is where the encoders are extracted when the order is received.

This part is intended for those who have broken the shafts in Infiniium series oscilloscope front panels. This is a rare part that cannot be ordered separately from the front panel. 

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