Specifications:

• Driver Unit: 21mm Planar Magnetic
• Sensitivity: 100± 3dB at 1kHz 1MW
• Frequency Responses: 20Hz ~ 40kHz
• Impedance: 32Ω± 15% at 1kHz
• Distortion THD: 0.8% at 1kHz 1MW
• Maximum Input Power: 1W z
• Working Voltage: 3.7V

Advantages：
World smallest planar earphone
Machined aluminum alloy
Memory steel of ear hook 
Columbia ear-tips