Upgrade path

Trap Window Store Four Sided Full→ 4× Wood →Plain Wood Window Plug→ 4× Wood →Window Plug 03→ 10× Cobblestone Rocks →Cobblestone Block→ 10× Concrete Mix →Concrete Block→ 10× Forged Steel →Steel Block

Hit a placed block with a stone axe, claw hammer or nail gun while carrying the material of the next step: 4 hits per upgrade.

Drops when destroyed

Where to find (20 POIs)

Haven Hotel (tier 5), Navezgane County Jail (tier 5), Ostrich Hotel (tier 5), Pop-N-Pills Factory (tier 5), Shamway Factory (tier 5), Shotgun Messiah Factory (tier 5), Two Bit Tower (tier 5), Diamond's Mens Club (tier 4), Downtown Marketplace (tier 4), Olgiddy & Brother Advertising (tier 4), Pineballs Bowling (tier 4), Stand Tower (tier 4), Johnson's Warehouses (tier 3), OK Laundry (tier 3), Poopy Pants City Daycare (tier 3), Triad Medical (tier 3), Marvin's Restaurant (tier 1), Booze Vault, Circuit Splits Station, Zillion Tower.

Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.