Sony MDR-E821V

Fontopia in-the-ear design fits snugly, yet comfortably inside the ear; eliminates the headband so you can enjoy music while exercising, skating or dancing
Volume control on headphone cord for handy adjustment on-the-go; uses special rotary/slide micro design
Sony Acoustic Twin Turbo Circuitry uses sound chamber and ducts for improved efficiency, gets high sonic output from your portable stereo
Silent Cap prevents sound leakage, makes your music less likely to disturb your neighbors
Neodymium magnet for maximum energy in minimum size; ounce for ounce, Neodymium is far more powerful than conventional Samarium Cobalt or Aluminum magnets
13.5 mm Diameter Driver is small enough to fit inside your ear
PET diaphragms ensure high rigidity for minimum distortion; low mass for extended high-frequency response out to 22,000 Hz
Compact case neatly stores the ear-buds and headphone cord when not in use; ideal for carrying in a pocket or purse
Type Lateral, In-the-ear, Open-air, Dynamic
Driver Unit 13.5mm diameter
Diaphragm PET
Magnet Neodymium
Cord Y-Shaped, 3.3 feet (1.0m)
Plug L-Shaped, Stereo Mini Plug
Impedance 16 ohms
Sensitivity 104dB/mW
Power handling capacity 50mW
Frequency Response 16 - 22,000Hz