# How to Put on the Chest Strap

{% hint style="warning" %}
Before putting on the chest strap, <img src="/files/jN4uRFbsF8ZtASQrhawz" alt="" data-size="line">**moisten the electrodes (the rubberized part)** with water or ECG gel.
{% endhint %}

<figure><img src="/files/cCDQFLDeRffErAdyLBZz" alt="" width="375"><figcaption></figcaption></figure>

1. **Prepare the chest strap and snap on the sensor**\
   Check that the chest strap is in good condition and that there is no visible damage. Carefully snap the sensor onto the chest strap.
2. **Moisten the electrodes**\
   Before putting on the chest strap, moisten the electrodes on the back of the strap with a small amount of water or ECG gel.
3. **Fasten the chest strap**\
   Fasten the chest strap so that the sensor is at the centre of the body (between the nipples) and as far below the breasts as possible. The belt should be tight enough to hold firmly. Make sure that the electrodes are placed directly on the skin and are not covered by clothing.
4. **Check the connection and sensor orientation**\
   Ensure that the sensor and chest strap are not reversed. The sensor’s numbering should face upwards, and the sensor’s logo should not be upside down. Also, in the **Kardi Ai** <img src="/files/zzPQbuThPSqv8jmzbQV0" alt="" data-size="line"> app , make sure that the chest strap is correctly connected to your phone via Bluetooth - when properly connected, the text **Ready for recording** will appear in the app.
5. **Start measuring**\
   Once the strap is properly fastened and connected, you can start measuring in the **Kardi Ai** <img src="/files/zzPQbuThPSqv8jmzbQV0" alt="" data-size="line"> app .
6. **Monitor strap fastening**\
   Regularly check during use to ensure the strap fits comfortably and does not become loose.

{% hint style="success" %}
After correctly fastening the chest strap, ensure that the measurement data is displayed in the **Kardi Ai** <img src="/files/zzPQbuThPSqv8jmzbQV0" alt="" data-size="line"> app and **keep your phone close to the chest strap**.
{% endhint %}

***

{% hint style="success" %}
**Need help?**\
Contact Kardi Ai customer support\
☎️ [**+420 779 998 100**](tel:+420779998100)\
✉️ [**support@kardi.ai**](mailto:support@kardi.ai)
{% endhint %}


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