The square key for the Keychron K3 (may fit other Keychron keyboards, but I only own the K3).

STL is orientated to print on the key's top. Would recommend extending the wall count to have a nice uniform look. If printing on a glass bed you can print on a raft to prevent the glassy finish. The button has a flat surface and not a concave shape on the key face. This was done to prevent any post-print finishing. With a concave shape you would need to print with supports, regardless of orientation, and then sand by hand.

If you would like to edit the STL you can rotate 108.5 degrees to have an up-right orientation.

This is a work in progress. Will look to include additional key shapes.