Gosky Precise Metal Bahtinov Focusing Mask for Telescopes Dew Shield or Front End Diameter From 83mm to 116mm （3.5"- 4.5" ） for More Precise and Faster Focusing[Product Information]- Enter your model numberto make sure this fits.
- The Bahtinov Mask Made of aircraft aluminum， not plastic. And it has whole anodizing aluminium process.
- Masks now feature 4 holes which can be attached with 4 screws to prevent the mask from falling all the way to the ground
- The Bahtinov Mask makes it perfect to focus of your CCD， DSLR or Webcam in seconds.
- Light weight so you wont upset the balance on your scope.
- Suitable for telescopes front end diameter 83mm to 116mm （3.5"- 4.5" ） ， Universal adaptation， 4 bolts with plastic cover allow the mask to be simply attached to any telescope
