Whether you’re mixing a recording or monitoring a bass line, you want earphones that deliver high-definition bass and super-transparent highs across an ultra-wide dynamic range. SD251-BT in-ear monitors fulfill your need to compose your own tunes in peace, no matter where you are – at a price that is very kind to every budget! 3 sets of ultra-soft earplugs provide perfect fitment for all ears with lasting comfort. When fully charged, SD251-BT provides up to 7 hours of music playback. They come with high-quality USB charging cable for quick charge on the go. A low battery voice prompt is also built in for convenience.