BaK-4 Prisms with Phase Coating: Increases contrast and resolution for sharper more detailed images. ,- Fully Multi-Coated Optics: Allows maximum light transmission through the optical path for brighter images. ,- Compact and Lightweight: Fits in a pocket or glove box. Easy to carry on long excursions. ,- Twist-up Eyecups: Twist up and down with multiple stops for correct positioning of the users eyes for comfortable viewing with or without eyeglasses. ,- Polycarbonate frame: Strong and durable polycarbonate body. Provides structural integrity while keeping the weight to a minimum