Also very well thought out, as the upper part of the assembly. but I have a couple of issues: 1: Too many magnet slots since the thing can't even retract that far. Magnet slots leave little gaps where air is sucked in, so the useless lowest slots need to be filled after printing. Better to not have them in the first place. 2: Too much play in the upper part. The tolerance could be lower, this part could be bigger and fit better. The corner-radii don't seem to match, too much air is lost.