Ricoh Pentax 8.5x21 Papilio Binoculars

Named for the Latin word for butterfly, PENTAX Papilio 8.5x21 binoculars are the perfect choice for insect observation in the field and in museums and galleries. The enhanced observation capability of the Papilio binoculars is made possible by a PENTAX Convergent Lens Optical System Engineering (CLOSE) mechanism. The CLOSE mechanism automatically slides the left and right objective lenses toward the center when the focus is fixed at a short distance.Specifications Binocular Type:  Center focusing, porro-prism Lens Construction:  Objective Lens: 2 elements in 1 group Eyepiece Lens: 5 elements in 5 groups Magnification:  8.5x Objective Lens Diameter:  21mm Real Field of View:  6.0 degrees Apparent Field of View:  50 degrees Field Of View At 1000 Meters:  105m Field of View at 1000 yards:  315 ft. Exit Pupil:  2.5mm Eye Relief:  15mm Prism:  Porro Minimum Focusing Distance:  1.6 ft. Relative Brightness:  6.3 Diopter Adjustment Range:  +/- 4 m -1 Diopter Adjustment:  Right diopter ring (click diopter adjustment) Eye Width Adjustment Range:  2.2 - 2.9" Focusing Range:  1.6 ft. - infinity Eyepiece Ring:  Helicoid Type Body Color:  Black & dark gray Dimensions:  4.5 x 4.3 x 2.2" Weight:  10.2 oz. Accessories:  Eyepiece lens caps, Case, Neck strap Vergence Correction:  Focus-coupled correction mechanism