Plumbing
Household Faucet
A metal thin block with 250 hit points.
Where to find (4 POIs)
Flushing Rule Palace (tier 4), Working Stiff Superstore (tier 3), Working Stiff Tools (tier 2), The Presley Dwellers (tier 1).
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.