This earbuds frequency response up to 20Hz-40KHz (usually 20Hz-20KHz for other fellows) reproduces the delicate and fresh original sound and restores the beauty of vocals and musical instruments. The earbuds last up to 5 hours of listening time (varies by volume and audio files) from a single charge and get three recharges by the charging case.  Price drops from $59.99 to $29.99 with code "SPDFORSD". Shipping is free.