Accidental winding and retracting is prevented from occurring without requiring complicated operations. Accordingly, there are included: housings 1 and 2 incorporating an electro-acoustic
transducer element 3; an input cord 9 one end of which is connected to the electro-acoustic
transducer element 3; take-up means 14 and 15 incorporated in the housings 1 and 2 and energized to wind and retract the input cord 9 into the housings 1 and 2;
ratchet means 20, 20a, 22 and 22a interacting with the take-up means 14 and 15 and preventing the winding and retracting of the input cord 9 by the take-up means 14 and 15 as well as allowing the input cord 9 to be pulled out of the housings 1 and 2; cancellation means 22b and 25 canceling the prevention of the winding and retracting of the input cord 9 by the
ratchet means 20, 20a, 22 and 22a; and ear-hook means in which an ear-hook arm 7 for
hooking the housings 1 and 2 on the ear is energized toward the housings 1 and 2; wherein when the ear-hook arm 7 is away from the housings 1 and 2, the prevention of the winding and retracting of the input cord 9 by the
ratchet means 20, 20a, 22 and 22a is not cancelled.