Going through a box of estate sale remnants and came across this accessory. No actuation button, but makes a horn (?) sound when you hook the wires to a few volts AC.
However...
What's the shaft-gizmo that extends from one end of the housing? Looks like it should have something like a knob attached to it? We see a set-screw on an outer shaft. No instruction sheet found. We see the same shaft on other pictures (Ebay, et al) of the accessory, but cannot understand what it's for.
Any help, please?
Thanks!
KD
