This is the classic Twixt board game.    The pegs hold 3 bridges (should be enough) or 4 in a pinch.  The pegs have a hex bottom to fit a little more firmly, and they are slightly rounded for easy insertion.  The NE and SW boards are identical, I included both for completeness. Ditto the NW & SE, but they are different than the other two.  The small square is just to align the 4 pieces of the board.

https://boardgamegeek.com/boardgame/949/twixt

twixt_bigbox.stl is a box for it with a snap lid.  twixt_spine.3mf is a two-color spine and label to glue to the box.  It's an extra download, not the direct Bambu Lab import.