Army Green Iron Door
Press & hold Activate to lock it or set a combination. Upgrade & repair with a construction tool using the secondary action.
Upgrade path
Hit a placed block with a stone axe, claw hammer or nail gun while carrying the material of the next step: 6 hits per upgrade.
Crafting
Craft at Backpack · makes 1
Crafted as Iron Door: pick this one of its variants when you place it.
Forged Iron× 10
Harvest drops
Iron× 4-10
Taken apart with a harvesting tool (axe, pickaxe, shovel), before perks and tool bonuses.
Drops when destroyed
- Iron× 10
When it collapses
Falling, it leaves 
Scrap Metal Pile (75% of the time) where it lands.
Where to find (18 POIs)
Camp Hollow Point (tier 4), Coleman's Drive-In (tier 4), Fort Choppa (tier 4), Goldrush Station (tier 4), NDC Checkpoint One (tier 4), COC Chemicals (tier 3), Jim & Tim's Bullets and Booze (tier 3), Ranger Station Golf (tier 3), The Serrano Residence (tier 3), Weston Weigh Station (tier 3), BONG Auto Parts Manufacturing (tier 2), Federal Appliance (tier 2), McPherson UFO Museum (tier 2), The Shady Swine (tier 2), Camp Carwhal (tier 1), Hog Foot Village (tier 1), USA #1 Type Bunker, Weedle Bro Gardens.
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.