8mm to 12mm Rigid Clamp-On Couplings, Aluminum Shaft Coupling 32 Diameter 45 Length, Motor Shaft Coupler Connector for CNC Machine 3D Printer DIY Encoder

Fit perfect, nice tight tolerances

Worked as decribed

The media could not be loaded. I used this to attach my motor to my drive wheel (from a stroller) for my Halloween flying ghost display. Works perfect.

Perfect fit

I purchased this NEMA 23 motor mount here on Amazon https://www.amazon.com/gp/product/B09QRZ13J5/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 and was trying to find a coupling that would work. The first one I ordered, which was a different brand had screw heads that protruded so much that the coupling would not turn in the motor mount.THIS Sinoblu motor mount worked great! The heads are much lower profile allowing the coupling to turn in the motor mount. If you are using a heavy duty motor mount, get the Sinoblu.

They are a little snug on the 8mm side, but nothing that would cause any issue with assembly. I'm very glad that I was able to find this style as I do not like the spring style connectors.

Fits perfect as described

This coupler doesn't have a 2 mm range. It has nearly no range. At full open capacity, it's pretty much fixed at that width. Tightening the bolts does nearly nothing. Add insult to injury, the interior is plastic. So, even if you do manage to get the coupler to close a little, it doesn't keep its grip on anything that isn't also plastic. I tried inserting a metal rod in it as a crank shaft and the plastic wore out after about 20-25 turns.