This adjustable flattener works fine. It is definitely required for the GuideStar 61 as focus could not be achieved without it.

Bought this to go with my WO Zenithstar ZS61 and it marries seamlessly with the scope and provides a nice adjustable backfocus. Was a little mystified at first as to why it wouldn't rotate, but after chatting to the team at FLO it was noted that the clutch screws were over tight and after loosening them a fraction of a turn the unit allowed me to rotate my camera orientation. Great service for FLO and speedy delivery.

The adjustable flattener has the usual William Optics quality feel about it. It gives secure attachment for my Canon and Fuji cameras, when used with the appropriate adapters, and has allowed me to capture crisp images now that we have finally had some clear skies.

It works fine, does what it’s supposed to do. The tension screws really need unscrewing a lot before it can be rotated to set the framing angle but once discovered, it does work. It would be useful if either William Optics website or FLO mentioned that rotation was possible and how to do it.

As with all William Optics quality, quality quality.

I bought this Flattener as it has been designed for the above scope,and could be directly screwed directly onto the scope,theifore eliminating any slippage, or off axis alighnment that can occur when using a flattener that is a push in and grip method.
Again with WO the fit and finish is second to none,and the adjustabilty to be able to set easily the back focus is a real game changer.
Another nice touch is that the Flattener can also be rotated in order to be able to frame your targets better.
I would,nt be without it,and to me it justifys the extra cost ,and i can thoroughly recommend it.

Great quality scope, using it on my nexstar mount at moment getting 60 second exposures, can’t fault service from FLO, highly recommended.

I've used cheap third party 1x flattener before and couldn't get field corrected on APS-c size sensor. I've decided to buy dedicated one. What a difference. Perfect stars across the field of APS-c. Will try with full frame soon.
Don't hesitate. Get one for yourself

Well made as expected from William Optics. But why no instructions? Easy tofind on website but would expect at least a leaflet at this pricd. Thanks FLO for good service as usual.

Great service from FLO delivery was very quick. The item was well packaged to prevent damage to the high quality flattener.