This ND96 neutral density filter allows 50 percent of the visible light to pass through It can be screwed on to virtually any astronomy eyepiece or accessory that has 1.25inch filter threads Features a standard 1.25inch female filter thread on the other side; so it can be stacked with additional filters Fully Multi-coated: Astromania 10mm Super Plossl eyepiece is engineered with 2 sets of 5 element design with fully multi-coated; the high-quality optics that minimize internal reflections and improve contrast 52 Degree Field Of View: The eyepiece have a wider 52 degree field of view than most eyepieces with a 10mm focal length and 7mm eye relief to see more detail; You can choose eyepiece with the right focal length for your telescope model which are parfocal Brand Astromania