Automatic Testing of Feed Conveying Equipment (Polygon mesh 3D model) is available on CGTrader for $129. Original author: Lovano. Specs: 18233682 polys, 54701046 verts.
SLDPRT (SolidWorks, filesize: 113 MB), OBJ (OBJ, filesize: 1.34 GB), IGE (IGES, filesize: 207 MB), STP (STEP, filesize: 47.4 MB), STL (Stereolithography, filesize: 869 MB)