A new generation: exquisite design, improved operation The A1 utilizes a sandblasted aluminium alloyed chassis for a durable modern appearance and comfortable hand holding. A transparent removable back clip adapts the A1 to different usage scenarios in style. Plug and play instant audio improvement With higher power hi-fidelity output than smartphones, the A1 satisfies your need for more sound quality and quantity. High-quality electronic volume control The A1's volume buttons are made of Alps micro-switches for sensitive and reliable operation. Four EQ modes for maximum flexibility The A1 provides Flat, Bass1, Bass2 and Bass3 EQ modes, switchable simplly by briefly pressing the power button, allowing you to adapt the sound output to your earphones and your ears. Moreover the indicator light clearly indicates the present EQ mode. 3-colour status LED for clear indications The A1 status LED lights/ flashes differently in different colours in response to power-on, charging, low battery, full battery, etc.. allowing you to check its working status at a glance. Rechargeable Li-poly battery included play time: approx, 13 hours Specifications THD + N 100db (A-weighted) Frequency response 20Hz ~ 20kHz Recommended earphone impedance 16~100 Ohm Dimensions 42mm x 40.7mm x 9.4 mm Charging time < 90 mins Play time >13h (32 Ohm loaded) Weight 20g (including black clip) Output power > 78mW (16 Ohm loaded)