Specs seem to be as described. Purchased for use on the Lunt solar scope. Limited to comparing against only one other zoom from an established major brand and few mid to higher end fixed focal length EPs(Pentax XW, Baader Morpheus, ES). Optical quality for a mid priced lens is more or less on par with the fixed focal length EPs. Vastly superior to the zoom it replaced. At least for the shape of my eye socket/face, the eyecup forms a good seal against ambient light for solar viewing. 3 position to allow accommodation for individual differences in eye relief distances. Recommend if you don’t mind the relatively narrow field of views and not parafocal. Potentially nice zoom for binoviewers. Light, compact. Something under consideration.

Price is a bit on the high end if the look alike clones are identical. Only niggle is the stiff zoom ring. Really need to clamp down hard on the twist lock or compression ring screws of the 2-1.25” adapters.

In addition to H-alpha solar observation. Using it on the refractor for Lunar observation. Solid zoom for that application.

Great zoom lens for a great solar scope. Do much easier than switching out lenses for magnifying for detail

This is the first 'Zoom" eyepiece I have ever tried and I couldn't be happier! To go from low to high power with a simple twist is really nice. The views are crisp and sharp throughout the entire range with no backlash at all. Highly recommend this eyepiece!