The quality of the Bushnell H2O Waterproof Fogproof Roof Prism Hunting Binoculars shows as it’s 100% waterproof, O-ring sealed and nitrogen purged for reliable with a fog-free performance. BaK-4 prisms and multi-coated optics offer crisp clear images with improved light transmission. Non-slip rubber armor and Soft Texture Grip absorbs shock and provides a firm grip. 10x magnification and 42mm objective diameter; 12-foot close focus distance; 17mm eye relief. Large center-focus knob for easy adjustments; Twist-up eyecup.