This is a geared assembly with a 3-digit vreeder-roote counter, not shown in the photo is an output shaft that is tied to the knob in the front - it goes through a flange with an O-ring on it.  The graduated dial makes one full revolution per count on the vreeder-roote counter.  One rotation of the input knob is aproximately 15 counts 

what the heck did this come off of?