These are tiles for Hextraction!
There are 8 different variants of this tile; for all of them, a ball down the left channel opens the central channel, and a ball down the right channel blocks the central channel (or vice versa depending on the orientation of the shuttle).
Print 1 base tile, one shuttle, and two caps. If you have a tile with a hole in the middle (?O?), then use the unindented shuttle. If you have a tile with no hole in the middle (?X?) use the indented shuttle. If you have a tile with a hole on the left (O??), use the left curve cap, otherwise use a straight cap. Same thing for the right cap. Print, insert the shuttle into the slot, and attach the caps with four M3 screws. Make sure the caps are not upside-down; otherwise, the ball will not fit in the channel.
This is version 2 which fixes an issue where the center hole on ?O? tiles was too high up, causing the ball to get stuck on board clips.