Gridfinity Friction Fit Grid Fillers

I printed a couple of Preds Gridfinity box's but I wanted to fill in the top grids so less dust collects in the lids and easier to wipe down. However I didnt want to print a solid lid as that will limit flexability and re-use in the future basically this keep the lid grid intact just in case I need it. As a side bonus you can make patterns on your lid by printing different coloured tiles. 

I checked around a few fillers but they all seemed to be drop in loose fit I couldnt find a friction fit version that would stay in place when opening the lid (I'm sure someone will comment with a link to one). So I downloaded grizzie17's reference file and spent a little bit of time designing my own and then adjusting until I had what I think is a good friction fit. 

I've uploaded 3 versions of my filler, I found the 0.4mm (friction nodules protrude 0.4mm on each side) to be really nice firm push in fit for Pred's Box Lid, However if using them for flat fillers in a draw i'd go for the 0.35mm they still clip but you dont need finger nails of steel to get them back out.
If mounting these to Pred's box do support the underside of the lid when you pop them in. Print one in one size first and give it a try across a few grid spaces before commiting to a batch print. I've included a 0.45 version but so far its been to tight for me to use on anything but included so there is +- 0.05 around the 0.4. I do print at 0.2mm layer height and I suspect a larger or even smaller layer height grid might find the 0.45 more useful just depends how the slicer and print turns out.

Step files also included.

Onshape file here