3D Astro Bahtinov Focus Mask for QHY and Orion 30mm Mini Guide Scope # BM-34.50
Farpoint Adjustable Tri-Bahtinov Focus Mask - 2.5 Inch to 4.5 Inch OTA – FarpointAstro
Orion PinPoint Telescope Focusing Masks
Bahtinov Masks | OPT Telescopes
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Farpoint Astro Bahtinov Focus Mask for Celestron 6" SCT
Amazon.com : Astromania Bahtinov Mask Focusing Mask for Telescopes - FM60mm for a Tube Outer Diameter (OD) from 65mm-100mm - can be Mounted with The Brass Screws Inside or Outside The drawtube :
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How to Use a Bahtinov Mask | Easiest Way Focus Your Telescope