SKUs and inventory items are used to describe products and services in your storefront catalog. When a third-party coordinates a product's fulfillment, you only need to interact with the SKU resource.
However, when Digital River acts as a product's fulfillment coordinator, you'll need to create SKU-inventory item pairs and ensure their common attributes remain synchronized. How you create these pairs and maintain this synchronicity depends on whether you're using the client fulfillment model or the Digital River fulfillment model.
In the retail word, stock keeping units (SKUs) represent a unique set of numbers and letters that are used to identify, locate and track your product. They typically provide information on the most important characteristics of an item. SKUs aren’t meant to be universal. They’re almost always unique to your business.
For every digital and physical product in your catalog, you need to define and create a SKU. You can then send its identifier in
POST/checkouts requests. This is true whether fulfillment of the product is coordinated by Digital River or handled by a third-party. So, before generating orders, we recommended that you catalog all of your SKUs.
An inventory item represents a physical product. Your workflows only need to use inventory items when Digital River coordinates a product's fulfillment. When this is the case, how you interact with the Inventory Item resource and how you ensure that it's common attributes remain synchronized with the SKU its paired with, depends on whether you're using the client fulfillment model or the Digital River fulfillment model.