Custom fields are a feature of the premium version of the Ultimate Product Catalog that let you add extra fields to your products, which can be displayed on the catalog and product pages, and which can be used for filtering your catalog.
The custom fields are very versatile and can be used in many different ways. For example, you can create a field to specify the color of a shirt or the size of a bicycle, and let people filter the catalog based on a specific value, so they can more quickly find what they’re looking for. Or you can use it to upload a PDF instruction manual for a product, and link to it directly from the product page.
For more info on custom fields, please see the following sections: