ShareTextures allows you to download 3D models and textures for free with no limit on the number of copies, and all materials are CC0 licensed, so you can use them freely.

The first wave of models will offer 1,700 3D scans from 27 organizations in 12 countries. ... the models will be published with the license of CC0 Public Domain, ...

With Smithsonian Open Access, we’re increasing the public’s ability to use millions of digital assets—2D and 3D images and data. Open Access items carry what’s called a CC0 designation. This means the ...