Befenybay 2PCS 5mm to 8mm Aluminium Plum Flexible Shaft Coupling D20 L25 Connector Flexible Coupler for 3D Printer CNC Machine and Servo Stepped Motor（5x8mm）

5mm was small. Had to drill it out a little bit.

The machining is horrible. I dont know if its made of aluminum or plastic.

I could not get my Z axis screw drive to remain level with the vertical frame of my Ender 3 V2. This little gem solved the issue as the gel inserts between the lower and upper halves allow flexing and the Z axis rod now remains straight. Great solution for a minor issue. 2 sets to a pack so youll always have a spare on hand.

Took me some time to figure out what was causing the banding on my print. When I took the lead screw out and looked at the shaft coupler while it spun, you can easily see the top piece wobble, thought it was just a bad z-screw initially, but after replacing that first, it had to be the coupler.

I like the quick delivery and i use it for my project.

Semplicemente dopo averli installati sulla mia stampante 3d ho riscontrato un movimento delle aste filettate non trascurabile. Da una parte un po me lo aspettavo vista la natura del pezzo (due pezzi separati con nel mezzo del materiale plastico) ma non così tanto. Il problema secondo me deriva dal non perfetto allineamento tra il foro da 5 mm e quello da 8 e questo accentua le oscillazioni.

There are better couplings on Amazon. Not only do the allan keys bolts strip very easily but the orange part in the middle separates easily as well if you apply pressure to it, making it a useless coupling for a more heavy duty attachment. I now have to throw these out because I couldn’t allan the bolt to loosen it because it got stripped so bad and it’s not due to poor technique or have it too tight. It’s just cheap. Wouldn’t recommend

The 5mm side for the stepper was to small. I ended up stripping the bolts to get it tight enough.

They seem to work. Hard to test it. You have to take the Z rods out all the way to get it to go in. But thats a good time to clean them. The fitting is very loose at first and the screws are very hard to turn. I thought I was going to strip it. Then finally it turned and tightened. I thought I had the wrong size at first.

worked as it should and am well pleased