The 4-diopter lenspiece gives a magnification of approximately 1.25X at a nominal working distance of 8" (200 mm) with a useful field of view of approx. 3-1/4" x 4" (83 mm x 100 mm). The Model LC loupe mount consists of a lightweight clip which attaches easily to most prescription spectacle frames. The angled grips make it easy to attach and remove loupe without removing glasses. Soft, non-slip caps on the jaws of the clip prevent scratching of prescription lenses. Height and tilt of the loupe lenspiece can be adjusted as desired. The one-piece optical element of the Model LC loupes is designed with a fixed binocular angle, optimized for the power of the lenses; the lines of sight from each eye converge at an ideal working distance to provide low-fatigue 3-dimensional stereo viewing.