This is the Lumicon 2" Enhanced Aluminum Coating Mirror Diagonal. I had a new mirror put in it in February, 2002 so the optics are like new and perfectly collimated by Lumicon. The body is machined aluminum and extremely sturdy with threads for standard 2" filters. It is the set screw version and there is a cosmetic circumferential set screw mark where the diagonal is attached to your telescope - no effect on function. Has both end caps. Will sell for $115 shipped in CONUS or trade for a matched pair of Meade Super Plossls of 12.4, 15, or 20mm fl. Please feel free to e-mail with any questions.