Sign Canvas Corrugated Metal 3x2
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 (16 POIs)
Navezgane Athletics Complex (tier 5), Joe's Junction (tier 4), NDC Checkpoint Four (tier 4), Church Of The Blinding Faith (tier 3), Happy Sleep Motel (tier 3), HSP Distribution Center (tier 3), NDC Checkpoint Two (tier 3), NPD 3rd Division (tier 3), Vick Garrison's Pedipawn (tier 3), Weston Weigh Station (tier 3), Federal Appliance (tier 2), Crotalus Rest Area (tier 1), Marvin's Restaurant (tier 1), Arbor Loop Rest Area, Canis Lupus Rest Area, Rhythm & Brews District.
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.