The celestron upclose g2 7x35 binoculars in this birders starter kit have high quality optics and bk7 prisms for a sharp and clear view during outdoor activities they are central focusing with dioptre compensation as well as multi coated optics which increase light transmission and result in brighter images with high contrast levels the rubber covered aluminium and ergonomic thumb indentsfinger ridges provide a comfortable non slip grip complete with splash proof body strap and nylon