Pentax U-Series Compact Porro-Prism UP 8-16x21 Binocular Black. Uni-body construction means fewer moving parts to repair or replace on these economical Binoculars from Pentax. With Pentax U-Series Compact Durable Porro-Prism UP 8-16x21 Binoculars even distant images will seem close enough to touch. Compact durable and economical Pentax U-Series Compact Porro-Prism UP 8-16x21 Field Binoculars will last a lifetime. Specifications for Pentax U-Series Compact UP 8-16x21 Binocular: Manufacturer: Pentax Magnification: 8 - 16 x Objective Lens Diameter: 21 mm Prism System: Porro Prism Material: BAK4 Eye Relief: 14 - 11 mm Exit Pupil: 2.6 - 1.3 mm Field of View Linear: 26.5 m at 1000 m Field of View Angle: 3 - 5 degrees Optical Coating: Fully-Multi Coated Binoculars Focus System: Center Focus Twilight Factor: 6.6 - 1.7 Interpupillary Distance: 57 - 72 mm Close Focus: 9.8 ft Diopter Adjustment Range: -4 - 4 dpt Length: 4.4 in Weight: 10.9 oz Condition: New Package Type: Box Additional Features: Compact Binocular Included Accessories: Neck Strap Case Eyepiece lens caps Magnification Type: Variable Features of Pentax U-Series Compact UP 8-16x21 Binocular New fully multi-coated optics Inverted porro prism design Aspherical lens elements providing edge-to-edge sharpness High Quality BaK4 prism to enhance transmission and resolution Dual-axis single body design with synchronized eye-piece IPD adjustment Black rubber armouring Pull-up eyecups Centrally-located lockable diopter adjustment Package Contents: Pentax U-Series Compact UP 8-16x21 Binocular Pentax 61961: U-Series Compact Porro-Prism UP 8-16x21 Binocular Black