Acid hydrometers; Bathroom scales; Car video recorders; Directional compasses; Distance measuring apparatus; Electric navigational instruments; Electronic collars to train animals; Eyeglasses; Global positioning system (GPS) apparatus; Hygrometers; Microscopes; Photographic filters; Precision balances; Salinometers; Stands for photographic apparatus; Telemeters; Telescopes; Telescopic sights for artillery; Tripods for cameras; Wearable activity trackers