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

This Bahtinov mask is lightweight yet sturdy. It is made of solid black plastic, and it installs very easily. The adjustable screws have rubber caps that help fit the mask securely to the end of the telescope, and it is easy to remove. With this mask, I can quickly and easily find accurate and precise focus for astrophotography.

Good quality, works great. Packaged well

I like the adjustable feature of this mask. I was uncertain of the size for my 80mm refractor, so I decided to buy one that bracketed the aperature on my 550. It functions quite well and is very light weight. I would say good value for the money.

I bought this with my own money and received nothing from the company that makes this Bahtinov Mask. This is a beautiful piece of kit this Bahtinov Mask. Build quality is good at .082" thickness with perfectly clean edges. You would have to abuse this to crack it. I see a review that says the screws don't fit the slots and wonder if someone did not realize that this is a nut/screw set up and did not separate them as mine fit perfectly with screw on one side going through to nut on opposite side I also read a review that it did not fit someone's scope, on my Celestron 80mm GTL refractor I measured the outside of the lens shade which was 100mm and the inside was 90mm, I wanted to mount this on the outside so I ordered the Bahtinov Mask that would fit the 100mm requirement. It fits perfectly and although I have not used it yet I can see that it should work perfectly. This is no Williams Optics clear Bahtinov Mask for sure but it also isn't $60.00. I have no doubt it will work fine.

Point your telescope at a bright star (and zoom in with your camera if you can) and this simple device will help you get the perfect focus for your astrophotography! I was generally pretty good as focusing but a Bahtinov Masks helps to ensure I've got everything in perfect focus so I don't end up with any wasted deep sky photography sessions.

Worked fine the first time I used it and was able to achieve perfect focus, however, the screws/standoffs need to be loosened in order to adjust the fitment for different diameter lenses and will come loose and fall off unless you tighten them to the point that you can no longer unscrew them by hand. I lost one of the screws and rubber bumper at some point when packing up my gear after shooting.

Can't beat these for getting good focus. Fits my telescope without problem. Make sure to measure you tube, it's not going to be the same as your aperture.

It fits my MEEZAA 150MM Teflector telescope perfectly. It has 3 screws that go on the mask and are adjustable. You move them to center the mask over the front of the telescope. Then you tighten them down enough to hold the thin mask in place

Took a long time to arrive, and when it did it had a crack in it... Did not want to spend another 3 weeks waiting for a new one so I patched it up with epoxy...

Goed product, goede service van verkoper!

I am now able to focus my Bahtinov lens very easily now which now makes my life much more easier.

Adjustable and well made. Fit my new refractor easily. Would buy it again if I had to.

Works perfectly as expected. Just be sure to order for the outside diameter of your tube.