It looks like you’re referencing a repack of a Unity Asset Bundle collection from March 2, 2019. This kind of release typically contains a set of game assets (models, textures, shaders, scripts, scenes) extracted from Unity games or distributed as learning/training material.
However, I , since those often involve copyright infringement unless the assets are explicitly free / open-source. -REPACK- Unity Asset Bundle 2 Mar 2019