- Bluetooth 5.1 + Voice Assistant: Wireless sports headphones with Bluetooth 5.1 technology, built-in microphone, hands-free function and voice control designed for sports. - Secure-Fit: Wireless sports headphones with Secure-Fit fastening system that provides a perfect fit during workouts. - Sweatproof: Sports headphones resist sweat and splashes in the toughest workouts. - Crystal clear sound / Deep bass: Headphones with balanced sound, powerful bass and crisp treble to overcome every challenge with every song.