This is the device install in the backpack, the middle roller will be fixed with the coil steel cable.
IGE (IGES, filesize: 9.38 MB), IAM (Autodesk Inventor, filesize: 25.8 MB), PDF (PDF, filesize: 25.8 MB), IDW (Autodesk Inventor, filesize: 25.8 MB), DWG (AutoCAD, filesize: 25.8 MB), STP (STEP, filesize: 4.77 MB)