SV503 80ED telescope's objective lens features an S FPL-51 extra-low dispersion glass ED element, which virtually eliminates chromatic aberration. This results in the good color correction for an ED doublet lens.A thoroughly though-out design and high-quality mechanical components. This very special SV503 telescope provides astrophotographers, visual observers or nature watchers with bright, wide field views when observing starry skies or nature watching.SV135 fully multi-coated zoom plossl eyepiece zooms to any focal length between 7 mm and 21 mm - pick the better magnification for your subject. As a beginner; SV135 zoom eyepiece is good for starter astronomer!The SVBONY 2" uv ir cut block filter is required for all digital imaging with digital cameras; CCD cameras and an improved webcam; the UV-IR-Cut filter uses the latest coating technology to provide the great filter quality-and use lifetime; with a DSLR camera, CCD camera or telescope.