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!SV188P Dielectric Mirror Star Diagonal，1.25in nosepiece fits telescopes with 1.25in focusers. Accepts standard 1.25” eyepieces, filters, Barlow lenses and other accessories with a 1.25in insert barrel.If you're not sure if a light pollution filter will benefit you or not (and it probably will), this SVBONY UHC Filter is a relatively inexpensive way to find out. Best of all, once you have it you'll probably feel no need to pick up a pricier one since this one will likely meet all of your needs.