Decor and furniture
Sign Canvas Corrugated Metal 4x1
It's a sign. You write things on it.
Harvest drops
Iron× 10
Taken apart with a harvesting tool (axe, pickaxe, shovel), before perks and tool bonuses.
When it collapses
Falling, it leaves 
Scrap Metal Pile (60% of the time) where it lands.
Where to find (15 POIs)
Downtown Marketplace (tier 4), Flushing Rule Palace (tier 4), Happy Sleep Motel (tier 3), KLZ Radio (tier 3), Le Spank (tier 3), Midway Clinic (tier 3), NDC Checkpoint Two (tier 3), Weston Weigh Station (tier 3), Buffalo Blues Building, MeltDowns, Navezgane Outlets, Sapphire Square, Urban Style Shops, Willtronics Corner, ZBrews Row.
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.