Once your item has been posted to Sketchfab and you have a page on their site, you may enter that URL in the new field provided in the Steam Workshop when editing the screenshots and videos for your item. To include a Sketchfab preview, you’ll need to create a free account on Sketchfab’s website ( ) and upload your model there similar to how you go about posting a video to YouTube. This can be used to provide an interactive 3D presentation of your model, scene, or item that users can zoom, pan, or rotate around to get a better view of your submission.
Here’s an example from johnskyrim’s Doomhammer, a Skyrim weapon mod:
When preparing the Workshop page for your mod or item, you now have the option to include a 3D Sketchfab preview of your item along with your videos and screenshots.