50 mm Porro;Backlit illuminated liquid dampened magnetic compass. excellent navigational tool for land or sea.Horizontal and vertical etched reticle to help determine relative size of objects;Range finding dial calculates actual object distance or size.Completely waterproof ﾃδ｢ﾃ｢ﾂつｬ dry nitrogen charged and sealed with internal O-rings to prevent internal fogging - unaffected by climate and temperature changes;Excellent depth of field for minimal focus adjustments.Nautical style padded canvas case and straps;Attached objective caps.Tripod adapter fitting for tripod mounting;Backlit illuminated liquid dampened magnetic compass ﾃつｿ excellent navigational tool for land or sea;Individual eyepiece focus;Rangefinding dial calculates actual object distance or size;Completely waterproof;Horizontal and vertical etched reticle to help determine relative size of objects