The casings for two ear-pads are adjustably mounted on opposite ends of an arcuate headband by means of a pair of rivet-like elements, each of which extends through an elongate slot in one end of the headband, and a central opening in the associated ear-pad casing. Each rivet-like element has an enlarged-diameter cylindrical head on its inner end and an enlarged, rectangular head on its outer end which is slidable in a correspondingly shaped recess in the headband to allow adjustment of each cas...