William Optics 1.25" 90° Dielectric Coating Diagonal

4.0 The Perfect 1.25" Diagonal

Dielectric coating, Polished to 1/10th wave accuracy, Carbon Fiber side plates, Internally anti-reflection threaded

The 1.25” barrel is tapered, not recessed

Great diagonal! It came with the purchase of a WO ZenithStar 66 SD APO and it's a match made in heaven. This dielectric coating diagonal will give you all you need for any type observations with its great brightness, contrast and sharpness. I was using a regular diagonal for years but I have seen the light - 99% of it. It is strong and well made but yet light. And it has a brass compression ring to prevent marring. A beautiful piece of art and science. One minor problem is that the 1.25” barrel is tapered, not flat with a recess. The tapered barrel will make the the whole diagonal move (just a bit) unless you over-torque the thumbscrew.