Amazon.com : Astromania Bahtinov Mask Focusing Mask for Telescopes - FM200mm for a Tube Outer Diameter (OD) from 215mm-260mm - can be Mounted with The Brass Screws Inside or Outside The drawtube :
Bahtinov Mask 90mm - 3D Printable Model on Treatstock
How to Make Bahtinov Mask, PDF Templates - DeepSky Watch
BuckeyeStargazer TriBahtinov Mask for SCT/RASA Collimation and Focus - For Celestron Telescopes
Bahtinov Mask For Samyang 135mm Lens by dakloifarwa - Thingiverse