2PCS 8mm to 12mm Aluminium Plum Flexible Shaft Coupling Diameter25mm Length30mm 8x12mm Motor Connector Flexible Coupler for 3D Printer CNC Machine and Servo Stepped Motor（8x12mm）

Much better than the style that came on my machine.

Fit perfectly got my CNC RUNNING again without any issues.

The Zeberoxyz 2PCS 5mm to 8mm Aluminium Plum Flexible Shaft Coupling provides a reliable and high-quality solution for connecting different components in various applications, such as 3D printers, CNC machines, and servo stepped motors.One of the notable features of these couplings is their build quality. They are designed to offer a secure and flexible connection between shafts of different diameters, ensuring that power and motion are efficiently transmitted between components. The use of aluminum adds to their durability and reliability.These couplings are comparable to many similar products in the market, offering a dependable solution at a competitive price point. They serve their purpose effectively and are a practical choice for those in need of flexible couplers for their projects.In summary, the Zeberoxyz 2PCS 5mm to 8mm Aluminium Plum Flexible Shaft Coupling is a reliable and cost-effective option for connecting shafts in various applications. Their good quality and competitive pricing make them a valuable addition to your toolkit.

The 5mm motor shaft, and 8mm lead screw holes in these couplers are bored too large -- and the aluminum casting isn't flexible enough to tighten down the coupler onto the shafts without an *incredible* amount of torque on the included hex wrench. Won't be buying this brand again.

Overall, everything seemed pretty good about these shaft couplers. They might end up being a little fatter than I'll be able to use for the project I'm currently working on, though, so I may end up using a different style of coupler.My main comment, that I've also seen echoed by others here, is that the shaft holes aren't a tight fit, and that it takes a whole lot of force on the grub screws to tighten them down sufficiently. Test carefully when you get them to make sure that's not an issue for you.

Of the 2 pieces one of them fit properly, the other was too small to fit onto any of my ballscrew shafts. They are machined incorrectly. Sending them back.

nicely machined

They popped apart and I thought I broke them but you can pop them back together! The two pieces will pull apart while retracting if your design doesn't account for that. I needed to add spacers and a plate to prevent it.