Primary Arms SLx 3X Micro Magnifier 21mm Tube Flat Dark Earth. This new optic is part of Primary Arms SLx line. SLx optics built Primary Arms Optics reputation for innovation reliability and value. All SLx optics undergo rigorous field-testing during development to best serve users in any environment. Specifications for Primary Arms SLx 3X Micro Magnifier: Manufacturer: Primary Arms Magnification: 3 x Eye Relief: 2.4 in Field of View Linear: 35.2 ft at 100 yds Color: Flat Dark Earth Exit Pupil: 7 mm Package Contents: Primary Arms SLx 3X Micro Magnifier Primary Arms 510013: SLx 3X Micro Magnifier 21mm Tube Flat Dark Earth