A modular L-Shaped ruler.  This can be used to show the X and the Y dimensions of something on an online marketplace, or to show how big your 3d prints are on MakerWorld.  It has been made modular because of the print bed restrictions on Bambu printers.  A little bit of superglue will make the bond permanent, otherwise it can be friction fit to be taken apart.  Graduations every half inch. 

1 inch wide. 0.375 inches thick. 12 inches long each direction.