This is a custom dice tray for playing the "Chain of Command" wargame.
It includes, as well as the tray, pegs to keep track of your Force Morale and Chain of Command Dice, and small 8mm dice to be used with the last few spaces on the morale track, indicating the effect of dropping to that level of morale for your particular force.
I've also included a dedicated rack for the Orders Dice, so that they're less likely to be picked up and thrown with all the others. It's designed to fit 12mm dice.
Edit: I've compressed the tray a bit so that it fits more easily on the bed of my Ender 3.