This is a simple shroud for a pentel hi-polymer eraser ( see picture ). The paper shroud that my eraser came with fell apart so i made this to replace it. I used petg because its softer than pla but pla or abs should work fine. The dimensions of the cavity are 12.5x24x40mm. Might be a tight fit but i got my eraser to go in eventually. if you want to make a smaller version, just cut it down in prusa slicer with its cut feature. I hope you find this useful!