26Pcs SIMAX3D 3D Printer POM Pulley Wheels - Plastic Linear Bearing V Groove Roller Wheels for Creality Ender 3, CR-10, Anet A8, Mega S - Clear | Smooth Motion Upgrade for 3D Printing & CNC Machines

Once the wheels started to get worn-in the squeaking begins. Build up of white “dust” will gather on wheels and extrusion as they wear. This causes a horrible squeaking sound to radiate from the printer. Ended up getting rid of wheels and changed to linear rails instead.These are not exactly the same as the original bearing wheels that come in the printers, but work jut the same. They’re a split surface design that seems to last better than the black ones. They add a bit of visual flair to the machines and this pack is enough for 2 printers to be serviced. I really like these and expect longer life out of these. Great product.When your 3d printer starts acting up, it could be the wheels. The soft rubber sometimes develops flat spots, or they get too smooth and start slipping instead or rolling; so they should be considered a consumable item over the lifespan of the printer.If you suspect your wheels are giving you problems, a set like this will let you change them all out at once. Just remember that some of the wheels are mounted on eccentric standoffs; and you need to adjust them to the proper fit using instructions specific to your printer. Consult an appropriate YouTube video or the manufacturer website for the procedure.These wheels move smoothly when rotated. In terms of function they are the v groove style of 625zz linear bearings. Bearings like this always seem to have interesting uses given the form factor with the groove in the center.I've only begun the process of using these with my 3D printer but from my experience testing them they moved with no issues of roundness or issues turning so I'd feel pretty comfortable giving these a try. I have been curious to try these with other applications outside of 3D printing as well and given the large number per pack it seems like I'll have ample opportunity.So far so good, appear to be of good quality and well made. Durability...to be determined over long term use. I see no reason at this point that there should be any issues. They track straight roll smoothly and do not have easily measurable runout once installed.