A heavy duty padlock with a key hole.
This file was modeled in Blender 2.79. The textures are procedural. It is available witout textures as an OBJ and STL files.
The Blender model constrains the shackle to limited movement in the z-direction and rotation about the z-axis.
STL (Stereolithography, filesize: 6.4 MB), OBJ (OBJ, filesize: 5.2 MB), BLEND (Blender, filesize: 16.6 MB), FBX (Autodesk FBX, filesize: 3.26 MB), MAX (Autodesk 3ds Max, filesize: 14.7 MB)