Note: rotate the parts by 180 degree before printing.
I had issues with drafts (small winds) comming from sides at the build platform, on the left it came from fan which is cooling the H bridges. On the right it was comming from PSU. So I made the cover for PSU and small barier on the right.
Because the Z axis glider was held by socket 0.3mm deep. I was worried it could fell off. So the the draft holders are acting as the Z axis holders as well.
I seen already different designs but they require to take it apart. And mess with the mounting system of the steppers. I didn't wanted to affect anything, the screws are made with exact distance and putting some PLA in between could affect torque and how stiff the mount it, now metal againts metal they can be very tight so I don't have to worry that something will go out of alligment or get loose. Mine design slides on top of the existing design (no need to undo any screws) and it will just friction fit on top, because I missaligned some holes maybe by 0.2mm so it's harder to put on, which means it will held there without any screws. If you want thincker holder then just scale on Z axis. If you don't want the barrier on the left side, then just take the right side and flip it 180 (the holes and possitions are mirrored, so it should fit both sides).
The PSU cover directs the wind a bit to the back, as show in the photo is not obstructing the fan much, but it's enough to direct the air away. Without lot of wind got bounced back from close objects (wall) back to build platform and was cooling it down. Causing warping and other issues.