NightSky Bahtinov Focusing Mask for Telescopes 240mm for More Precise and Faster FocusingAll Metal Construction. Anodizing Aluminium ProcessThe Bahtinov Mask Made of Metal, not plastic And it has whole anodizing aluminium process.
NightSky Bahtinov Focusing Mask for Telescopes 220mm for More Precise and Faster FocusingAll Metal Construction, Anodizing Aluminium ProcessThe Bahtinov Mask Made of Metal, not plastic And it has whole anodizing aluminium process.
NightSky Bahtinov Focusing Mask for Telescopes 340mm for More Precise and Faster FocusingAll Metal Construction. Anodizing Aluminium ProcessThe Bahtinov Mask Made of Metal, not plastic.And it has whole anodizing aluminium process.