Brunton Eterna Elo 15 x 51 Binocular Lost Camo, One Size BaK-4 prism glass; State-of-the-art phase coating; AL reflective coating; Emerald Fire full multi-co Multi-step eye relief system Waterproof; Nitrogen filled/fogproof Ergonomic body armor; Tripod/monopod compatible Power 15X; Objective diameter: 51mm; Eye relief:15mm; Exit pupil: 3.4mm; weight: 32 oz