Hama Piano Blues. Device connectivity: Wired, Device interface: 2x 3.5 mm, Cable length: 2.5 m. Ear coupling: supraaural, Acoustic system: closed, Headphone frequency: 20 - 20000 Hz. Microphone frequency: 100 - 10000 Hz, Microphone sensitivity: -54 dB, Microphone input impedance: 2.2 Ом. Volume control: Rotary