Polar Equine H3 Belt Set Easy-to-use wireless heart rate sensor measures your horse's heart rate during training Ideal for measuring heart rate for longer periods when trotting and longing Adjustable fabric strap easily fits around your horse Compatible with the following equine units: CS600X Trotting, RC3 GPS Trotting, RC3 GPS, RS800CX GPS, RS800CX Science, V800 and V650 Includes H3 heart rate sensor and adjustable fabric strap