# Extending tagging with SKUs
Nosto supports individual product SKUs under parent products. If you have not set up [Product tagging](https://docs.nosto.com/techdocs/implementing-nosto/implement-on-your-website/manual-implementation/product-tagging) you should start there and extend the tagging if needed.
The SKU attributes should be listed on the last row of the `nosto_product` block that you have already implemented on the product pages.
**What is a SKU?**
Many e-commerce stores have a parent product with individual child products. The parent product is usually something along the lines of "Ski Jacket" whereas the SKUs would then be "Ski Jacket, Blue, Small", "Ski Jacket, Red, Medium". If your store uses SKUs you should add the following attributes to extend your product tagging.
```js
nostojs(api => {
api.setTaggingProvider("products", [{
...
skus: [
{
id: "1",
name: "S-Orange",
price: 1269.00,
list_price: 1299.00,
url: "http://www.example.com/product/CANOE123#/1-size-s/13-color-orange",
image_url: "http://www.example.com/product/images/CANOE123-1.jpg",
availability: "InStock",
custom_fields: {
size: "S",
color: "Orange"
}
}
{
id: "2",
name: "S-Blue",
price: 1269.00,
list_price: 1299.00,
url: "http://www.example.com/product/CANOE123#/1-size-s/14-color-blue",
image_url: "http://www.example.com/product/images/CANOE123-2.jpg",
availability: "InStock",
custom_fields: {
size: "S",
color: "Blue"
}
}
]
}])
})
```
or via DOM tagging
```markup
...
...
...
1
S-Orange
1269.00
1299.00
http://www.example.com/product/CANOE123#/1-size-s/13-color-orange
http://www.example.com/product/images/CANOE123-1.jpg
InStock
S
Orange
2
S-Blue
1269.00
1299.00
http://www.example.com/product/CANOE123#/1-size-s/14-color-blue
http://www.example.com/product/images/CANOE123-2.jpg
InStock
S
Blue
```
**Note:** The attribute `custom_fields` can contain whatever unique information for individual SKUs that you can consider helpful. Frequently used attributes would be size, color, material.
**Extending the cart tagging with SKU metadata**
When tagging the cart contents as outlined here, you can also tag information of the actual SKU that was added to cart.
```javascript
nostojs(api => {
api.setTaggingProvider("cart", {
[
{
product_id: "Canoe123",
sku_id: "1",
...
},
{
product_id: "Canoe123",
sku_id: "2",
...
},
{
product_id: "Canoe245",
sku_id: "1",
...
}
]
})
})
```
or via DOM tagging
```markup
Canoe123
1
1
Acme Canoe
999.00
EUR
Canoe123
2
1
Acme Canoe
999.00
EUR
Canoe245
1
3
Acme Large Canoe
19.00
EUR
```
Notice the extra `` attribute.
**Extending the order tagging with SKU metadata**
When tagging the order contents as outlined here, you can also tag information of the actual SKU that was added to cart.
```javascript
nostojs(api => {
api.setTaggingProvider("order", {
info: {
order_number: "1445",
email: "john.doe@example.com",
first_name: "John",
last_name: "Doe"
},
items: [
{
product_id: "Canoe123",
sku_id: "1",
...
},
{
product_id: "Canoe245",
sku_id: "2",
...
}
]
})
})
```
or via DOM tagging
```markup
1445
john.doe@example.com
John
Doe
Canoe123
1
1
Acme Canoe
999.00
EUR
Canoe245
2
3
Acme Large Canoe
19.00
EUR
```
Notice the extra `` attribute inside each of the `purchased_items`.
{% hint style="info" %}
To learn more about the `api.setTaggingProvider` usage, please refer to the [official API documentation](https://nosto.github.io/nosto-js/interfaces/client.API.html#settaggingprovider).
{% endhint %}
## Validating
Once included you can review if the SKUs are picked up by using the [Nosto Debug Toolbar](https://help.nosto.com/get-started/guides/how-to-use-the-nosto-debug-toolbar). If you can see individual SKUs being picked up below the original product details then this is correctly set up.
You can further verify that products are being indexed to the catalog under the Nosto admin by navigating to Tools → Products ()    
## FAQ
### Do I need to view events for when an SKU is viewed?
No, Nosto does no recommend individual SKUs. While this is something on our roadmap, at the moment, you do not need to send any events when an SKU is selected.
For example, assume you had a product page selling a shoe. In this case, the product tagging would always point to the id of the shoe. No events should be dispatched when the customer selects a particular size such as S, M, L.
---
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