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Universal Solar Filters (ULF) are cardboard filter kits for safe solar observation. They are based on the SolarLite Filter by Thousand Oaks. After assembly, the filters can be attached to the lens. They then attenuate the sunlight so far that a safe view of the photosphere with its sunspots is possible.
ULF-90: Fits most 80-90mm aperture telescopes and some larger camera lenses and spotting scopes. 90mm aperture, fits over outside diameters of 90-109mm. For smaller outside diameters, tabs should be folded inward to grip lens.
