Rugged Waterproof, Fog proof Construction. Bright, Multicoated Optics. Long Eye Relief for Eyeglass Wearers. Rubber Armored. Multi-Click Turn-and-Slide Eyecups. BaK4 High Index Prisms. Product Features Rugged Waterproof, Fog proof Construction Bright, Multicoated Optics Long Eye Relief for Eyeglass Wearers