Features: Metal composite membrane technology ensures high-fidelity sound quality, offering ultimate music enjoyment. Professional tuning method provides two kinds of music model: normal and bass. In-ear design helps to cut off ambient noise. Solid alloy shell is corrosion-resistant yet decorative. Built-in microphone is easy for you to answer calls. 3.5mm jack plug, compatible with most Android phones, and support part of the function for IOS devices.