New Original Rose Pink Crystal Xiaomi 2nd Piston Earphone/Headphone Headset Earbud with Remote & Mic for Smartphone - Rose Pink Crystal Piston design of the metal cavity, a high precision lathe knife molding With stable cavity structure, can effectively reduce the cavity resonance for the negative effects of sound quality Aluminum alloy resonant chamber Remote Control and Mic for smart phone. (Volume Control Doesn't work for iPhone) Better bass performance