The Eyepiece Filter Set - 1.25" from Celestron contains 4 assorted filters mounted in black anodized aluminum cells, packed in a plastic case. All 4 eyepiece filters are threaded to fit Celestron's, and most other manufacturers 1¼" eyepieces. The cells of each filter are double-threaded so that they can be stacked in different combinations. They offer a full 26 mm clear aperture. This filter set includes: Orange #21, Light Blue #80A, Deep Yellow #15 and 25% #96ND filters.
Celestron's filters are made of high quality, solid plane parallel glass. They have an anti-reflection coating to help prevent glare and aberrations. Not only are these highly useful filters and combinations, but they also provide an economical way to add versatility to your filter collection.