National Geographic 8x40 Porro Binoculars Now we are going to get a little bit bigger. These classic 8x40 binoculars are able to show you observed details, even from a long distance very clear. Let your journey of discovery begin. FEATURES � Lenses and prisms made from optical glass material (BK-7) � Centre focus � Rubber coated / lacquered � Diopter adjustement � Tripod connection threads � Porro prism systems � Objective lens diameter: 40 mm � 8x magnifi cation � Colour: Black Technical Data Optical specifications Magnification max. 8 ED glass 0 LE Eyepieces 0 Objective diameter (mm) 40 Material prismn BK-7 Eyepieces for eyeglass wearers 0 Diopter setting 1 Electronics, hardware & software Batteries included 0 General technical data Waterproof 0 Compass 0 Inert gas purged 0 Tripod adapter thread 1 Focusing system Central focus wheel Single eye adjustment 0 Zoom function 0 Warranty (Years) 5