Hello Hello Astromarters!
I have a 10mm Celestron SMA (Super Modified Achromatic, basically an improved Kellner) for sale. Says, "Wide Angle on the eyepiece." Specs are:
*6mm eye relief
*52 degrees apparent field
*Threaded for filters
Good condition, no set-screw marks but sticker is slightly peeling off. Comes with both end caps and box.
Great star party eyepiece!
$15 shipped CONUS via Priority Mail.