A pair of button boxes to support a mame arcade PC (for player 1 and player 2). You will need to print 2 of the top piece, and then one each of the player 1 and player 2 box. I purchased buttons from Amazon: https://www.amazon.com/gp/product/B00WAY9848/ref=ppx_yo_dt_b_asin_title_o09__o00_s00?ie=UTF8&psc=1 to fit into this box.