Metal hole. Beware of robotic termites.
The item id for Hole Metal in unturned is 376. You can use this ID with the commands below to spawn the item, give it to a player or buy it on a modded economy server.
Useable: Structure
Construct: Roof
Size_X: 2
Size_Y: 2
Size_Z: 0.45
Health: 1300
Range: 8
Explosion: 36
Blueprints: 1
Blueprint_0_Type: Structure
Blueprint_0_Supplies: 1
Blueprint_0_Supply_0_ID: 68
Blueprint_0_Supply_0_Amount: 5
Blueprint_0_Level: 2
Blueprint_0_Skill: Craft
Blueprint_0_Build: 27
PlacementAudioClip: Sounds/MetalPlacement.mp3
Has_Clip_Prefab: false