Doors and hatches
Red Steel Garage Door 5x3
Press & hold Activate to lock it or set a combination. Upgrade & repair with a construction tool using the secondary action.
Harvest drops
Iron× 750
Taken apart with a harvesting tool (axe, pickaxe, shovel), before perks and tool bonuses.
Drops when destroyed
Spring× 8-12
Mechanical Parts× 8-12
When it collapses
Falling, it leaves 
Wood Debris (Terrain) (75% of the time) where it lands.
Where to find (2 POIs)
NFD Downtown HQ (tier 4), Fire Station 7 (tier 2).
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.