To use Klaviyo Product Feeds and Product Blocks in emails, you need to link up your product catalogue by following the instructions below:
1. Copy this URL from the Klaviyo For Neto admin page:

2. Log in to your Klaviyo account
3. Visit this hidden URL where you can manage your catalogue sources: https://www.klaviyo.com/catalog/sources
4. Click Add Source
5. Fill in the information about your catalog:
Name – the name of your custom catalog – e.g. “Neto Product Feed”.
URL – enter the url from step 1
Username and Password – Leave these blank
6. After filling in your custom catalog information, click Add Source.
7. Click on the name of the feed you just added to edit the feed.
8. Klaviyo will show a warning about the $categories field. Change this to categories.

9. Click Update Field Mappings
10. That’s it! Your product catalogue will be available within a few minutes.