Headset

A headset combines a headphone with a microphone. Headsets are made with either a(n) single-earpiece (mono) or a(n) double-earpiece (mono to both ears or stereo). Headsets provide the equivalent functionality of a telephone handset but with handsfree operation. They have many uses including in call centers and other telephone-intensive jobs and for anybody wishing to have both hands free during a telephone conversation. (source)