Each item in Minecraft has a unique ID assigned to it, known as an item ID, this can be used in commands to spawn the item into the game. The item ID for diamond horse armor in Minecraft is shown below:
Items from earlier versions of Minecraft were assigned a numerical ID - a unique number to represent it.
The numerical ID for Diamond Horse Armor is:
The Diamond Horse Armor item can be spawned in Minecraft with the below command. Cheats must be enabled before this will work.
Horse armor acts exactly like regular armor for players, but can be equipped by horses and provides them with extra defence.