Microscopes; Telescopes; Binoculars; Distance measuring apparatus; Height measuring instruments; Magnifying glasses; Optical apparatus and instruments, namely, optical ports for underwater photography, dome ports for underwater photography, wet diopters, adapter lenses for underwater photography; Optical frames; Optical lenses; Periscopes; Precision balances; Protective eye pieces; Sighting telescopes for firearms; Surveying apparatus; Surveyors' levels; Telemeters; Telescopic sights for arti...