You can setup the materials as an asset library using Blender's asset browser feature.

Open Blender's user preferences, and go to, file path, then, Asset Library's. Click on the plus icon, and then choose the folder where you are storing the product's Blender files. Make sure to save the user preferences. Then you can open Blender's asset browser window and access the models in your projects.

If you don't know how to setup and use the asset browser, you can watch my setup guide tutorial video Here.

Using Blender version 3.4 or a newer version is highly recommended. Some of the objects materials will only work properly in Blender version 3.4 or newer, due to the updated Mix Node in Blender, which will not work properly in any versions older then 3.4.
▶️ Watch my video about the new Mix Node here.
▶️ How to Fix the Mix RGB Undefined Node Tutorial