Relays won’t fall out. FreeFlex secure fit is simple to use. Adapts to any ear size without the need for complicated parts or ear hooks. Tuned for Workouts. Great music through great sounding headphones is like sonic energy. Noise isolating in-ear speakers with powerful rich bass and clear vocals delivers all the emotion of your favorite workout songs. Ultra slim fit design rests comfortably in the ear even for long workouts. In-ear noise isolation. In-ear tips seal the ear, blocks out outside noise, so you can hear the full sound of your music. Sweat and water-resistant. Even in the sweatiest of workouts your Relays Sport will keep your music playing. Microphone and music control. The inline microphone and remote make it easy to play/pause your music, take calls – or activate Siri or Google Assist. 3 button controls volume for Apple devices.