GE 12729 toggle switch q

Does anyone know what the horizontal button underneath the toggle switch of the GE 12729 does? It toggles left and right and haven’t figured out what exactly it does. Manual does not say either.I haven’t installed the switch yet.

I don’t have those, but could it be an air gap switch? That allows you to fully cut off power to the switch because even though the switch is off, it still pulls power to stay alive and work in your mesh network.

That should be the air gap switch.

That makes a lot of sense. Thanks!