Good shot MReyn,
You got it. Argentinian Marquis de Pateras Pescara produced several Helicopters - this one being Model 3 - that had the contra-rotating 'biplane' rotors.
Honourable mention to dook who nailed the fact that this was the first to successfully demonstrate true cyclic pitch control.
Note the Batman wings over the cockpit to prevent rotor ingress to pilot head in the event of break up.
Bloody brave souls.
