ROCK Zircon Stereo Earphone Brand: ROCK Unit: 1Set Connectors: 3.5mm Function: Noise Cancelling, Microphone Cord Length: 1.2m Speaker Sensitivity: 93+-3dB (at 1KHz 1mW) Rated input power: 1Mw, Maximum input power: 3mW Microphone Sensitivity: -40dB+-3dB@1kHz,0dB=1V/pa OPERATION TEMPERATURE: -10C~+55C Speaker: 8 mm (8 mm NdFeB speaker) IMPEDANCE: 16ohm +-15% Speaker Frequency Response: 20-20K Hz Package: Simple Packing