Review on SINYUM 608 2RS Skateboard Bearing 8X22X7 by Andre Motko

They all have a very noticeable wobble when you move them in your hands. On a skateboard or inline skates, that means excessive heat and wear, not to mention what I can see through "shields" meaning they're unsealed. I think it's worth buying higher quality bearings. However, I use them for my 3D printing projects and they work well for what I need. A professional tip, 8mm, is about 0.002" more than 5/16", so a 5/16" aluminum or steel rod with epoxy fits in very nicely!