Scientific models and specimens, namely, X-ray image analysis simulators, for use as teaching aids for training skills of inspections of X-ray radiographic image or X-ray computed tomography image; planimeters; measuring rules; gravimeters; densimeters; profile projectors; graduation checkers being calibration checkers; screw-thread measuring machines and instruments; metal compression testing machines; metal hardness testing machines; metal strength testing machines; rubber testing machines;...