Specifications for Nikon Prostaff 3-9x40 Camo Realtree Shockproof Riflescope: Actual Magnification: 3x-9x Objective Diameter: 40 mm Exit Pupil: 13.3-4.4 mm Eye Relief: 3.6-3.6 in Field of View(ft at 100 yds): 33.8-11.3 Tube Diameter: 1 in Eyepiece O.D.: 39.3 mm Length: 12.3 in Weight: 13.1 oz Adjustment Gradation: 1/4 MOA Max Internal Adjustment: 80 MOA Parallax Setting: 100 yds tr>