# Add serial numbers to the Shopify POS cart

## Adding the "Serialize cart" UI extension

{% embed url="https://www.youtube.com/watch?v=hG-vnPPo_CQ" %}

In the Shopify POS mobile app, tap:

Add tile > App > Serializer - Product Tracking > Serialize cart > Save

## Using the extension

{% embed url="https://youtu.be/YFSzQHiBM3U" %}

1. Add products to the Shopify POS cart
2. In the app extension, select the product variant to serialize
3. (Optional) Adjust the product quantity by scanning the product barcode or using the plus (+) and minus (-) buttons
4. Enter the serial numbers or [custom fields](track-custom-item-information).&#x20;
   1. Type serial numbers separated by a comma, space or new line, e.g. "s1,s2", "s1 s2" or \
      "s1\
      s2"
   2. Or scan the serial number barcodes
5. Save the changes
6. Check out and complete the transaction - the saved serial numbers will appear in the admin version of the app after a short delay (usually in less than a minute)

{% hint style="danger" %}
The POS extension uses order line properties (also known as custom attributes) to synchronise serial numbers from Shopify POS cart to the app database and Shopify order metafields. **Please do not delete the order line properties with keys "SN" or any other keys prefixed with "serializer\_" until the saved item information appear in the app.**
{% endhint %}
