Upgrade path

Wood Shutters Outside→ 1× Iron Shutters →Iron Shutters Outside→ 1× Steel Shutters →Steel Shutters Outside

Hit a placed block with a stone axe, claw hammer or nail gun while carrying the material of the next step: 5 hits per upgrade.

Crafting

Craft at Backpack · makes 1

Crafted as Wood Shutters: pick this one of its variants when you place it.

Harvest drops

Taken apart with a harvesting tool (axe, pickaxe, shovel), before perks and tool bonuses.

When it collapses

Falling, it leaves Wood Debris (Terrain) (75% of the time) where it lands.