> For the complete documentation index, see [llms.txt](https://supercartapp.gitbook.io/supercart-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://supercartapp.gitbook.io/supercart-docs/other-features/checkout-validations.md).

# Checkout Validations

### How to enable?

Visit your Shopify Admin Section and click on the Checkout tab.

<figure><img src="/files/nRBBrBcuPCaKaGOXBtnG" alt=""><figcaption></figcaption></figure>

Scroll down to Checkout rules. Click on Add rule and select the Supercart validation.

<figure><img src="/files/d74vbTW0MMGLqKVgCzgH" alt=""><figcaption></figcaption></figure>

Now you can turn on the validation.

<figure><img src="/files/iuqz4i9ltCyMOvrFmwzG" alt=""><figcaption></figcaption></figure>

### Result

The customers are not allowed to purchase Extra Services as single products.

<figure><img src="/files/gyqGzhKh6vKLIeKvqKD8" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/eT9kD1EgHIXlvV8NjQq2" alt=""><figcaption></figcaption></figure>