Features MO-FI is a headphone with a built-in amplifier that pursues the best sound quality in any situation. You can enjoy the best sound quality with any device, from professional studios to mobile devices and smartphones. It features a unique multi-joint ear cup design that breaks away from conventional ideas, and boasts a wonderful design. Specs ＜Features＞ ■ Built-in high-quality headphone amplifier ■ 3 types of analog amp modes ■ Innovative design for comfortable fit ＜Specifications＞ ■ Type: Semi-open ■ Driver: Dynamic, φ50mm ■ Frequency Response: 15～20,000Hz ■ Impedance: 42Ω ■ Weight: Approx. 466g ■ Accessories: ・Soft case with cable storage pocket ・1.2m audio cable with Apple iPhone/iPad control function ・Warranty card ・English manual ＜Amplifier Section Specifications＞ ■ Output Power: 240mW ■ Distortion Rate: 0.004% ■ S/N Ratio: 105dB or more ■ Noise: 20uV or less ■ Battery Capacity: 1020mAh ■ Continuous Playback Time: Approx. 12 hours ■ Charging Time: Approx. 3-4 hours Missing items from the original purchase ・3m audio cable ・1m USB charging cable ・3.5mm to 1/4 inch TRS adapter ・2-pin connector for in-flight use * The above items are not included. The photos are all that is included. I am selling this item because I have hardly had a chance to use it. Please understand that this item has been stored at home before purchasing.