Astronomik SII 12nm CCD MaxFR Clip-Filter for EOS R XL circle " or "best" answer doesn't

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3mm Product Weight 38g

--Electron-beam gun evaporation with Ion-assisted deposition coating technology (IAD) increase the stability of CWL (central wavelength)

it is free use in the world

Astronomik SII 12nm CCD MaxFR Clip-Filter for EOS R XL circle " or "best" answer doesn'tAstronomik SII 12nm CCD MaxFR Clip Filter EOS R XL MaxFR Astronomik photographic narrowband emissionline filters for fast optical systems. There is an ever growing demand for filters suitable for extremly fast optical systems like Celestrons RASA the Epsilon Astrographs made by Takahashi. Our novel MaxFR emission line filters are suitable up to very fast focal ratios. The new Astronomik MaxFR series of narrowband emissionline filters is perfect