Barska 12X50mm Porro Prism Binoculars Rubber Armor Blue Lens Black. The wide variable magnification range of these binoculars allows the viewer to target in on an object and then zoom in and magnify it to obtain a closer look and see greater detail. For convenience all models also feature a zoom thumb lever for making quick and smooth zoom adjustments as well as fold-down eyecups for viewing with or without eyeglasses. Specifications for Barska 12x50mm Porro Prism Binoculars Blue Lens: Manufacturer: Barska Color: Black Magnification: 12 x Objective Lens Diameter: 50 mm Prism System: Porro Prism Material: BK-7 Image Stabilizer: No Eye Relief: 11 mm Exit Pupil: 4.17 mm Field of View Linear: 275 ft at 1000 yds Optical Coating: Fully Coated Binoculars Focus System: Center Focus Twilight Factor: 24.49 Close Focus: 22.96 ft Weather Resistance: None Length: 6.89 in Weight: 30 oz Finish: Rubber Armor Included Accessories: Carrying Case Neck Strap Magnification Type: Fixed Tripod Adaptable: Yes Size: Medium Nitrogen Filled: No Brightness Index: 17.38 Compass: No Eyecups Types: Fold Down Housing/Frame Material: Aluminum Armoring: Rubber Armored Case: Yes Strap: Yes Zoom: No Features of Barska 12x50 Binoculars Blue Lens: Magnification: 12x Objective Lens: 50mm Prism Type: Porro Prism Glass: BK-7 Exit Pupil: 4.17mm Optical Coating: Fully Coated Focusing System: Center Field of View: 275at 1000yards at12x Close Focus Distance (m): 7 Eye Relief: 11mm Weight: 29.5 oz. Package Contents: Barska 12x50 Binoculars Blue Lens Carrying Case Neckstrap Lens Cloth Barska CO10675: 12X50 Porro Prism Binoculars Blue Lens Black