This is the Medisana FUSE Heart Rate Activity Tracker crimson (red) L [MS-79428] • EKG-accurate heart rate data, with no chest strap required • Tracks steps, pace, distance and calories to provide a complete assessment of your daily effort • Customizable display and configurable heart rate zones • Connects to fitness apps with Bluetooth Smart (4.0) • Sync heart rate to bike computers & GPS watches via ANT+ • Stores activity data and wirelessly syncs to the Mio GO app • Water resistant to 30m (3ATM) • Mio FUSE Crimson fits large wrist sizes: 156 -208mm/6.1â€-8.2†...Contact us if you need more help.