Designed with athletes in mind, the blue JBL Reflect Fit Heart Rate Wireless Headphones feature an ergonomic neckband design, heart rate monitoring capability, and IPX5 sweatproof construction. These Bluetooth in-ear headphones utilize 5.8mm dynamic drivers, which help deliver JBL's 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.