The Koss BT190i Wireless Bluetooth FitBuds feature energizing wireless sound designed specifically for sports and fitness. The Wireless Bluetooth FitBuds are designed with sweat resistant technology and unique in-ear clips ensuring that your music moves with you even during the most rigorous of exercise. Intuitive, on-board controls allow listeners to quickly navigate through songs, play or pause music, volume-up and volume-down; listeners can also stay connected using the in-line microphone to easily answer incoming calls. The built-in rechargeable lithium-ion battery delivers up to 6 hours of play time (at moderate levels) and 80 hours of standby time on a single charge. Soft silicone in-ear cushions seal comfortably around inside the ear to block outside noise and keep music from leaking out. Frequency range: 20 Hz - 20000 Hz, Finish: White