A phone is a very different animal than it was just a few short years ago. You can use it as a GPS, you can shop online, and now, it even functions as a heart rate monitor. So if you're ready to make the jump, the Tate Labs Bar Fly iPhone HRM Bundle lets you mount your iPhone 5 securely to your bike, and use it to track your workouts. The Bar Fly fits to any handlebar with a 31. 8mm clamping diameter. The rotating phone mount allows you to mount your phone vertically or horizontally, to optimize the display for your needs. This kit includes a waterproof hard case for an iPhone 5, as well as a 4iiii heart rate monitor. It's also compatible with ANT displays, such as Garmin, for example. When it's set up, it allows you to use your iPhone 5 to track your heart rate. In other words, your training just got a lot more precise.The Tate Labs Bar Fly iPhone HRM Bundle is available in one size, and in the color black.