Terralux TT1-EX tail switch questions

[AJH_CUSTOMS]

the TT1-EX uses a 2 button tail switch having a round forward clicky main switch and smaller mode switch.
My questions is what the circuit looks like? Normally the tail switch is a single switch that completes the GND path. what or how is the smaller mode switch connected? Is it connected to the controller? How?

Thanks in advance.
Aaron