The optical system uses extra-low dispersion (ED) glass to ensure accurate color reproduction and to virtually eliminate color fringing. The lenses are fully multi-coated to provide optimal light transmission and feature a phase-coated BAK4 roof prism. The Endeavor 65A comes with a 65mm objective lens and an angled eyepiece with 15x to 45x zoom magnification. It has a retractable, rubber-coated eyecup and offers an impressive eye relief even at the highest zoom settings. Additionally, it provides a very impressive field of view.