That’s it on the left, next to a standard MIDI cable plug. The whole thing is so small it fits inside a MIDI plug and can run off the power supplied by the MIDI output, driving a small pizeo buzzer.

From the Aiguille du Midi cable car descend down the ridge and continue to Col ... Climb to the right of the ridge on a rock and snow slope of (small section of mixed climbing where the slope steepens ...