William Optics Diffraction Spikes Bahtinov Focusing Mask - For Telescope Tube/Dewshield Diameter from 243-308mm (9.57"-12.13")

Stock count is accurate & shown in real time.
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
Contiguous US / Lower 48:
Free shipping applies to orders over $50 using our chosen carrier/method. Faster paid options are available at checkout.
Alaska, Hawaii & US Territories:
Free shipping applies to many—but not all—products. Enter your ZIP code in cart or upon checkout to confirm options and costs.
International:
International orders do not qualify for free shipping. Shipping, duties, brokerage, tariffs, and taxes are the customer’s responsibility. Some items may be restricted due to export, size, or manufacturer limitations.
William Optics' Diffraction Spikes is an ultra high optical transmission Bahtinov mask which produces the clearest, brightest and longest diffraction spikes facilitating focusing with ease and accuracy.
- Optical transmission: 92% and above (about 3 times brighter than traditional metal masks)
- Made with optical grade PMMA acrylic material
- Easy to mount on many telescopes that have an outside tube or dewshield diameter of 243mm – 308mm (9.56" – 12.13")
Other Information
- Country of Manufacture: Taiwan
William Optics' Diffraction Spikes is an ultra high optical transmission Bahtinov mask which produces the clearest, brightest and longest diffraction spikes facilitating focusing with ease and accuracy.
- Optical transmission: 92% and above (about 3 times brighter than traditional metal masks)
- Made with optical grade PMMA acrylic material
- Easy to mount on many telescopes that have an outside tube or dewshield diameter of 243mm – 308mm (9.56" – 12.13")
William Optics' Diffraction Spikes is an ultra high optical transmission Bahtinov mask which produces the clearest, brightest and longest diffraction spikes facilitating focusing with ease and accuracy.
- Optical transmission: 92% and above (about 3 times brighter than traditional metal masks)
- Made with optical grade PMMA acrylic material
- Easy to mount on many telescopes that have an outside tube or dewshield diameter of 243mm – 308mm (9.56" – 12.13")
Other Information
- Country of Manufacture: Taiwan

William Optics Diffraction Spikes Bahtinov Focusing Mask - For Telescope Tube/Dewshield Diameter from 243-308mm (9.57"-12.13")
