I replaced my old bench grinder with a new one and decided to 'upgrade' the old one with a new wire wheel and adding a buffing wheel. The old grinder's housing was a bit too close (IMHO) to add a buffing wheel so I installed the EmilyPro shaft extension (the longer version).Fit and finish was (barely) acceptable - the interior of the extension staff was burred and had to be cleaned up before it would slide over the grinder arbor shaft. In addition the retaining nut (13/16 o.d.) did not thread onto the EmilyPro arbor shaft until I cleaned up the shaft threads. Quality control may not be quite the best I've ever seen.Once installed (simple installation, remove the old grinding wheel, remove the grinder's guard, slide the EmilyPro onto the grinder arbor shaft, secure with the included hex screw using the included hex wrench, install the included retaining washer, install the buffing wheel, install the second included retaining washer, and thread on the retaining nut. Note that the EmilyPro I installed was for the right side of the grinder.After reading reviews I was concerned about vibration but that turned out to be not a concern - there is some vibration but not enough to cause a problem. YMMV.I'd recommend the EmilyPro, but with the caveat that you may run into quality control issues so don't expect necessarily a plug-n-play solution. I'd also recommend not making any alterations to the adapter that would prevent you from sending the unit back in case there are vibration issues.Including the cost of the new wire wheel and the EmilyPro and I added functionality to my basement shop for about $40 - better than sending the old grinder to the recycle yard. Total time to upgrade the grinder (including cleaning up the EmilyPro threads and inside shaft) was about 30 minutes.I added this motor shaft extension to an electric motor and it worked well for my application.Unfortunately, it came with only 1 nut. I need 2. Unable to find a nut with matching threads,This does the jobIt works as intendedIt workedthis adapter is well made, the threads to tighten your wheel is made with a relief at the thread end this allowed the wheel to be off center. the quick fix was to install an "O" ring in the groove . works well.I had a non-treaded 1/2" shaft motor that I wanted to attach a cutting wheel to.This works beautifully and comes complete with an arbor adaptor, a nut for the threaded shaft extension, and an Allen L-key hex wrench. Delivered quickly.