3D spectacles; Accelerometers; Audio- and video-receivers; Baby monitors; Camcorders; Cameras; Cinematographic cameras; Clinometers; Computer hardware; Directional compasses; Distance measuring apparatus; Gradient indicators; Inclinometers; Infrared detectors; Range finders; Scanners; Slope indicators; Smartglasses; Stereoscopes; Surveying chains; Surveying instruments; Telemeters; Wearable activity trackers; Electric or electronic sensors for image; Electric or electronic sensors for motion;...