Pentax S-Series Superior SP 16x50mm Full Size Porro Prism Binocular Black. Ruggedly styled with a full-rubber housing including the extra large central focusing wheel. They feature exceptional optical performance including high quality BaK4 prisms. The S-series consists of both roof and porro prism models with objective lenses > 40mm so personal preferences are immediately defined. In addition to the newly developed light transmission coatings waterproof porrro prism models also boast the hydrophobic coating thereby allowing for contrast-rich bright viewing under rough outdoor conditions. Specifications for Pentax S-Series Superior SP 16x50 Full Size Binocular: Manufacturer: Pentax Color: Black Magnification: 16 x Objective Lens Diameter: 50 mm Prism System: Porro Prism Material: BAK4 Eye Relief: 13 mm Exit Pupil: 3.1 mm Field of View Linear: 18.6 m at 1000 m Field of View Angle: 3.5 degrees Optical Coating: Fully-Multi Coated Binoculars Focus System: Center Focus Twilight Factor: 9.8 Interpupillary Distance: 58 - 71 mm Close Focus: 30 ft Diopter Adjustment Range: -2 - 2 dpt Length: 4.7 in Weight: 32 oz Finish: Black Package Type: Box Additional Features: Full Size Binocular Included Accessories: Eyepiece lens caps Neck Strap Case Magnification Type: Fixed Features of Pentax S-Series Superior SP 16x50 Full Size Binocular New fully multi-coated optics Durable aluminum die cast body High Quality BaK4 prism to enhance light transmission and resolution Fully rubber armoured body Large central focus wheel For spectacle wearers: soft rubber eyecups that can easily be folded back Click-stop diopter adjustment Package Contents: Pentax S-Series Superior SP 16x50 Full Size Binocular Pentax 65905: S-Series Superior SP 16x50 Full Size Binocular Black