... , 3.5mm Aux in, USB powered,Class D amplifier, 50% higher power efficiency,Max 2W / Ch, ... two Φ40 mm micro drivers to deliver stunning sound. The speakers make use of the high ... efficiency of class D amplifiers to present excellent sound quality.Specification:Power output: RMS 1W*2Driver: ... high efficiency of class D amplifiers to present excellent sound quality. Specifications Drivers: 1.5", 4ΩInput ...