Designed with athletes in mind, the Black JBL reflect fit heart rate wireless headphones feature an ergonomic neckband design, Heart rate monitoring capability, and IPX5 sweat proof construction. These Bluetooth in-ear headphones utilize 5.8mm dynamic drivers, which help deliver JBL signature sound quality. On-device controls let you adjust volume and playback, and a vibration alert system will notify you when you're receiving an incoming call. The reflect fit's built-in battery lasts up to 10 hours and can deliver an hour of playback off a quick 15-minute charge. Three sets of eartips, a carry pouch, and charging cable are all included.