Sketchfab is a popular platform for sharing and discovering 3D models. If you're in need of an OBJ file for use in your projects, Sketchfab makes it easy to download them. Here's how to do it:

1. Find the 3D model you want to download on Sketchfab.

2. Once you've found the model, look for the 'Download' button. This is usually located near the 3D viewer.

3. Click on the 'Download' button and choose the 'OBJ' format from the available options.

4. If the model has multiple files, you may need to download a zip file that contains the OBJ file along with any other related files.

5. Once you've downloaded the OBJ file, you can import it into your 3D modeling software and start using it in your projects.

It's as simple as that! With Sketchfab's easy-to-use interface, downloading OBJ files for your 3D modeling needs is a breeze.