OctagonStar Flexible Couplings 5mm to 8mm NEMA 17 Shaft for RepRap 3D Printer or CNC Machine（2PCS）

I dont usually write reviews but felt this nice addition to my printer deserved one. I recenrly bought a Kingroon KP3s for my niece and nephew for Christmas. Ive been tuning it the last month or so and just replaced the z coupler with one of these. Literally 3/4 done first print with it. Back to back, calibration cube with old and new coupler and what a difference. From what I read - make sure you dont put the 8mm lead screw in too much as same as the stepper rod- so the middle area of the coupler can flex and do its job.Just wanted to give an A+++ reiview quick. dont hesitate to buy. Quality control atleast of the one I got was on point. Fit like a glove. Also love that you have 2 screws on top and 2 on bottom vs the factory one which had 1 top 1 bottom..Good luck and happy printing

I love these flexi connectors. My Ender 3 has a z-rod that isnt quite straight and caused issues. This helped!

Chinsium alloy

Works perfectly

WORKS GREAT

was a gift for someone,

Got 2 of them, one work and other one dead in one month.

These seemed like a very good part initially. At least they did a good job initially, but I've had two of them fail on my steppers driving lead screws. I've got an alignment problem, or the holes in the couplers aren't on center. i'm not sure which. Just be careful with them. If you see any signs of misalignment as you rotate the shaft, like the space between the slots in the couplers changes as you rotate the shaft, it's probably not going to last very long.