This is a custom 8-way restrictor plate for an arcade joystick.The joysticks I got for my arcade cabinet (http://www.arcadewinkel.nl/joysticks/balltop-arcadefighter-stick-rood) were fine, but I wasn't entirely happy with the restrictor plates that came with it. They worked fine in 4-way mode, but the 8-way mode was simply a square and that doesn't work nicely in most circumstances.From what I can tell, the screws are placed differently on all joystick brands, so YMMV if you have a different one. I included the scad file if you want to play around with it (but it's not nicely parameterized).There's not really much to instruct here: