Two-pack of elastic chest straps for heart rate monitoring. Comfortable and adjustable elastic chest straps. The chest straps are made of high-quality materials and fit snugly against the skin. The soft fabric and adaptive electrodes are extremely sensitive to the electrical signals from the heart. Compatible with multiple heart rate sensors (ANT+, Bluetooth 4.0, 5.3K). This comfortable heart rate chest strap is compatible with [product]. The smart combination of soft fabric and adaptive electrodes makes it extremely sensitive to [product]. As an integrated part of a heart rate monitor, it can accurately detect your heart rate and transmit it to your smartphone in real-time. The world's most popular heart rate strap, easy to use and very reliable. Snap fastener. The chest straps are made of high-quality materials and fit snugly against the skin. Snap fastener. Model: Heart rate chest strap. Distance between the two snap fasteners: 0.45 cm (Check your transmitter's distance and confirm compatibility). Color: Black. Material: Nylon/Polyurethane. Size: Approximately 98 cm in length. Package contents: 2 adjustable elastic straps. Only the above package items are included; other products are not included. Note: Due to lighting conditions and different monitors, the color of the item in the picture may differ slightly from the actual item. Measurement error is +/- 1-3 cm.