FISTERS MGN12H Linear Sliding Guide/Block 350mm CNC 3D Printer

I was excited by the appearance of the first I opened. Black block ends with oil hole that actually works. They were the right tolerance for my rails. There is a small defect in the plastic ball return that causes it to click pop / a restriction. Then I opened the next one green ends. Strange. Clicks too.

Its an OK linear bearing. It does have some play so it is not really as solid as I would have liked it to be but it is doing a good job on my 3D Printer.It is noisier than v grove rollers on 2020 extrusions.

Meh, it's got more than a few thou of play in it. Got this for my 3d printer, but I'm debating going back to wheels until I can find a linear rail with minimal play.