Features: Adopt double bass diaphragm resonance technology, clear sound quality, providing immersive music experience. HD voice call, smooth and no delay. Intelligent automatic noise reduction, effectively reduce environmental noise, restore real sound. Ergonomic in-ear design, fit the ear canal, comfortable to wear. Soft wire, easy to store and hard to break. High-quality 3.5mm interface, anti-oxidation, anti-rust, enhances the stability of signal transmission. Adopt pure copper core, avoid noise, stable transmission. Specification: Brand: Lenovo Model: TW13 Color: Black Type: Wired in-ear headphone Interface type: 3.5mm Microphone sensitivity: -42dB±3dB Frequency response: 20-20000Hz Speaker sensitivity: 100dB±3dB Speaker diameter: 10mm Impedance: 16¦,±15% Cable length: 1.2M±10mm Item weight: Approx. 13g /0.46oz Packing list: 1 * Headphone 2 * Pairs of earplugs