What does this electrical symbol mean?

[b*saint]

Im not sure really. It has a tiny tiny plunger but it looks like a prox switch. The machine does use switches to set home position on all axes. The switch sits in a recess and you can't actually watch it work. As far as I know, the switch isn't in the Pilz circuit.

[b*saint]

Ok so I figured out how the switch works. First of all there has to be a 24v signal sent to the PLC to let the PLC know which type of head is on the machine (welding or light duty cutting or heavy duty cutting.) That's where the common wire is feeding from. Next there is a B axis mirror present which has to energize the coil of two latching relays before the drive can be enabled. The first relay is wired so that A1 is the feed coming from the "B-axis mirror present" connection A. The second relay is power by the 24v bus and the other side (A2) is series through "B-axis present" connection B then through the "-" terminal on the switch that I originally posted, thus completing the circuit to enable the 2nd relay on. Maybe that explanation makes sense maybe it doesnt lol but thats how its working now.