GQCQGS Headphone Amplifier - Two Stage Gain Switch 3.5mm Aux

Description: This delicate, compact, lightweight and portable HiFi headphone amplifier, can improve the sound quality of your smartphone, making it possible to view pure stereo sound without distortion. It's worth it! Specifications: Output power: Max: 300mw * 2 / 300mw * 2 / 300mw * 2 / 300mw * 2 / 300mw * 2 / 16Ω Frequency/Response: 2-27KHZ 27KHZ Signal to noise ratio: 95 dB Dynamic range: 90 dB Separation: 70 dB Distortion: ≤0.00 6% Input impedance: 32 Ω Output impedance: ≤ 200 Ω Operating Temperature: -40℃~60℃ Storage temperature: -40℃~85℃ Storage Humidity: 10%~90% Battery: Built-in lithium battery, 200mAh (charged by a micro USB cable) Battery resistance: approx. 30 hours Size: 70 x 25 x 10 mm / 2.76 x 0.98 x 0.39 inches. Color: Grey (shown as pictures) Package weight: 40g Package list: 1 x HiFi amplifier (excluding charging cable) 1 x HiFi amplifier (charging cable excluded) Note: Headphone amplifier ONLY improves sound quality, can NOT increase volume.