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. 

William Optics Diffraction Spikes Highlight:

• Optical transmission: 92% and above 
• Made with optical grade PMMA material
• Easy to mount on 3" – 4.2" refractor telescope 

William Optics Diffraction Spikes includes:

1. William Optics Diffraction Spikes Bahtinov Focusing Mask suitable for OTA outer diameter of 105-148mm

Comparison with traditional Bahtinov mask