Has anyone used that 0.5X focal reducer designed for 1.25" eyepieces? They just thread-on eyepieces like a filter. I grabbed two of them on eBay from China for under $40 for the pair, thinking of a possible strategy for doubling my bino-viewer magnification range without buying more eyepiece pairs. No instructions or literature came with them at all. They just arrived yesterday and of course I can't try them out immediately. Maybe tomorrow on a terrestrial target.