This is a mount/holder for a USB controller used in a MAME kit I ordered on Aliexpress.

http://www.aliexpress.com/item/Arcade-mame-DIY-KIT-FOR-2-players-PC-PS-3-2-IN-1-to-arcade-joystck/32595240925.html

The controller card is 40 x 50 mm in size, and I added ca 1 mm to the dimensions. The bottom is rised 2 mm so that the soldered components have some space in the bottom.

The stl file is in metric (mm).

As a finish I drilled a couple of holes and threaded them for M3 to mount the board to the holder.