Description from Orangetheory site: This isn't just a heart rate monitor. It does more than that. It tells you when to push yourself. It tells you when to rest. And when your workout is working. This is a life-changing monitor. Compatible with the Orangetheory Fitness app for use during in-studio, at-home and out-of-studio workouts. The OTbeat Burn measures distance, calories, and your unique heart rate data so you can get the most of your workout. It has a sleek, black band that can be worn on your forearm, or bicep. The box includes a gently used OTbeat Burn heart rate monitor (used for less than 10 classes) Two breathable black armbands (one already on the monitor and an extra in the box as pictured in the listing) Mini-USB Charging Cable Please note: This item contains a lithium ion battery and will have to be shipped according to USPS standards and guidelines.