[The to track results] V6 accuracy 1 bpm. Stop guessing what your training intensity should be. Our heart rate monitor provides real-time analysis of your heart rate and calories burned during exercise. The V6 chest heart rate monitor is very reliable. [Multifunctional] Fits all athletes with adjustable strap from 26 inch to 38 inch, Under tension maximum length is 39 inch to 70 inch.The V6 chest strap has been tested by professional marathon runners, mountain enthusiasts and mountain . It shows that V6 helps them get an accurate heart rate, thereby helping them achieve their best exercise state. Wear a monitor when , biking, hiking, yoga, running, indoor or outdoor training. [Wide compatibility] Support Bluetooth 5.0 and ANT+.Compatible with hundreds of fitness applications, including for , Beat, Zwat, Runtastic Pro, Run Club, iCardio, , etc. Compatible with for iOS mobile devices: for 5 and higher, iOS 11 or higher. An Android mobile device with Bluetooth 4.0 function and Android 5.0 or higher. [Wearing ] 1. Moisten the electrode area of the chest strap with water; 2.Wear it on your body before pairing it with your device, your heart rate will powers up the monitor so it will be detected by your Bluetooth;3.Pair the sensor via the Bluetooth of your fitness app, it 't work properly if adding it directly from the Bluetooth of your cellphone; 4.Connect with sport watches,When pair this sensor with your watch please turn off the watch's own heart rate monitoring function. [Quality] V6 heart rate monitor chest strap is waterproof, sweat-proof and dust-proof (IP67 waterproof, but not suitable for swimming). Built-in replaceable CR2032 button battery, working time is 12 months. Easy to replace, use a coin to unscrew and replace the battery. Material:ABScolour:black Package Contents: 1 * computer heart rate belt Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.