Full title reads: "Paris. The Super Air Detector. It records flying speed, altitude and location of enemy aircraft."
Weird looking gadget being used by French soldiers to check for enemy aircraft. Two men sit with earphones on listening to the sounds amplified by the detector. The move it round to follow the sound of aircraft. CU one of the operators. Tilt up to the listening device. Various shots of this odd looking device. CUs of operators.