21A Light Red 1.25" Telescope Filter - (25% transmission) Enhances Detail In The Belts And Polar Regions Of Jupiter and Saturn - Helps You See Mercury During Daylight Hours By Increasing The Contrast Between The Planet And The Blue Sky - Includes Clear Safety Case

Eyepiece filters are an invaluable aid in lunar and planetary observing. They reduce glare and light scattering, increase contrast through selective filtration, increase definition and resolution, reduce irradiation and lessen eye fatigue. These filters are made of high quality, solid plane parallel glass with excellent homogeneity. They are anti-reflection coated to prevent glaring and ghosting. All eyepiece filters are threaded to fit most 1.25" eyepieces and offer a full 26mm clear aperture. Comes with a hinged, plastic case to keep your filter safe and clean when not in use.