Does anybody know what this is?

[Sunny]

I know what they are, they came off a puzzle table so they can hold puzzle pieces by color as you work on it.
My DH has a puzzle table with thoseView attachment 475552

I have the same puzzle table. The sliding drawers are rectangular with square corners, so I knew it couldn't be that. But I never would have guessed what it turned out to be.

About the table, if any jigsaw puzzle fans are thinking of getting one, here's a warning: their sizes are very exact. I always do 1000 piece puzzles but mistakenly got the 1500 piece size. It's way too big. I was too lazy to bring it back to the store, so I just kept it, but I would have been much happier if I had gotten the correct size.

 

[IrishEyes]

I have the same puzzle table. The sliding drawers are rectangular with square corners, so I knew it couldn't be that. But I never would have guessed what it turned out to be.

About the table, if any jigsaw puzzle fans are thinking of getting one, here's a warning: their sizes are very exact. I always do 1000 piece puzzles but mistakenly got the 1500 piece size. It's way too big. I was too lazy to bring it back to the store, so I just kept it, but I would have been much happier if I had gotten the correct size.

My DH's table came with 4 of those foldable squares for extra piece holders, they are color coded though,

 

[RambleTamble]

I still don't know where those rubber tray things came from. Weird.

 

[OldFeller]

Perhaps a hat of some kind. Like those worn by Monty Python.