Transparent uppers/mids balanced by rich low-end qualities combine with advanced acoustic engineering for extensive performance capabilities and highest quality Dual-diaphragm capsule design maintains precise polar pattern definition across the full frequency range of the microphone The 2-micron-thick, vapor-deposited gold diaphragms undergo a five-step aging process so that the optimum characteristics achieved remain constant over years of use

Comfortable & Security Fit -- Custom designed in ear mini bluetooth headphones, lightweight , security in ear, very convenient to use when driving, exercise and a lot of occasions Super Long Using Time -- Bulit in 90 mah big capacity Li-ion battery ,energy saving tech, charging mini bluetooth earbud 2 hours get up to 10 Hr music time( about 60% max.volume) . Premium Sound Quality -- With in ear Hi-fi sound quality , Strong Signal & Built in Mic ,you can enjoy music and answear phone calls with this mini bluetooth earphone more easily