YOTINO5PCS Flexible Couplings 5mm to 8mm NEMA 17 Shaft Coupler for Creality CR-10 CR-10S S4 S5 Makerbot RepRap Prusa i3 3D Printer Or CNC Machine(Bonus 1pcs M3 Allen Wrench)

I bought it to replace the old and stretched coupler on my Tevo Tarantula. They are pretty much the same as the stock one.The improvement in quality is noticeable, probably not because of the quality of this product (don't get me wrong, they are great) but because my old coupler is quite damaged.If you are having z band issues, this could be the problem.Left tower was printed with the old coupler. You can see the difference compared to the one on the right

If all you need is to attach some steppers to an 8mm shaft, these are for you. They've got entirely too much play for my purposes, and on to parallel steppers, my screws have an unacceptable amount of play due to these. The lash is not something you can compensate for. 2 stars cause it's just okay and I didn't have to wait forever for them to come in.

I used to have threaded rods which would translate to my prints causing z-banding, but once I finally installed these and also re-tuned my steps. The print quality was definitely improved

Low quality aluminum; way to soft for a Z axis on a printer

Upgraded 2 printers and these are great!