Compatible with heart rate sensors: Works with MZ-3.<br> Adjustable sizing: Belt circumference 66cm (adjustable), width 3cm.<br> Easy to use and clean: Utilizes snap attachment method. Sensor transmitter must be removed and soft strap hand-washed as needed.<br> Comfortable and functional: Made of nylon material, attaches closely to skin. Soft fabrics and adaptive electrodes for sensitive detection of heart's electrical signals.<br> Note: Only strap, heart rate sensor transmitter not included. Color as shown in the picture.<br> For the heart rate belt, center distance of buttons is 45mm. Please confirm the button distance on the back of heart rate module before purchasing.<br> Package Contents: 1 * Strap. Only the above package content, other products not included.<br> Note: Light reflection and different displays may cause color variation. Measurement allowed error is +/- 1-3cm.