Barska Colorado 7-21x40mm Zoom Binoculars. These Barska binoculars feature a powerful reverse porro prism that allows for high-resolution viewing with edge to edge clarity and optimum brightness improved by the Colorado's fully-coated lenses. These binoculars are capable of functioning at a range of powers from 7x to 21x giving you the ability to look at objects that are miles away or just down the path. The Barska Colorado 7-21x40 Reverse Porro Prism Binocular has a center focus knob on the bridge that allows you to make fast and smooth adjustments a common feature on these Barska Outdoor Binoculars. Barska has equipped the binoculars with a durable and ergonomic rubber armor that has non-slip properties to keep the binoculars in your hands even when the terrain gets rough. For a pair of rugged compact binoculars that can go everywhere you do choose the Barska Colorado 7-21x Variable Power Binoculars. Specifications for Barska Colorado 7-21x40mm Zoom Porro Prism Binoculars: Manufacturer: Barska Color: Black Magnification: 7 - 21 x Objective Lens Diameter: 40 mm Prism System: Porro Prism Material: BK-7 Image Stabilizer: No Eye Relief: 14 - 12 mm Exit Pupil: 5.5 mm Field of View Linear: 90 ft at 1000 yds Optical Coating: Fully Coated Binoculars Focus System: Center Focus Twilight Factor: 16.73 - 28.98 Close Focus: 32.8 ft Weather Resistance: None Length: 5.5 in Weight: 26.46 oz Included Accessories: Neck Strap Lens Cloth Carrying Case Lens Cover Magnification Type: Variable Tripod Adaptable: Yes Size: Small Compass: No Eyecups Types: Fold Down Housing/Frame Material: Aluminum Brightness Index: 30.25 Case: Yes Nitrogen Filled: No Strap: Yes Zoom: No Armoring: Rubber Armored Features of Barska Colorado 7-21x40mm Zoom Binoculars Versatile outdoor binoculars by Barska Variable power magnification from 7x to 21x Compact and rugged body design Non-slip rubber armoring Reverse BK-7 porro prism for high-clarity viewing Fully-coated optics improve brightness Easy to use center focus knob Comes with a carrying case Backed by the Barska limited lifetime warranty Magnification: 7-21x Objective Diameter: 40mm Angle Of View: 7x - 5.2; 21x - 2.9 Field Of View: 270' Close Focus: 10m Exit Pupil: 5.5mm Relative Brightness: 32 to 3.6 Eye Relief: 7x - 14mm; 21x - 12mm Lens Coating: Fully Coated Lens Color: Blue Prism Type: Porro Prism Prism Coating: BK-7 Focusing System: Center Focus Body Material: Rubber Finish: Black Included Accessories: Carrying Case Package Contents: Barska Colorado 7-21x40mm Zoom Binoculars CO10686 Carrying case Barska CO10686: Colorado 7-21x40mm Zoom Binoculars