User Summary: The Sewer Wall Pack is part of the City Builder System. The Sewer Wall Pack is made of "Dwarvenite". This item was initially available during the City Builder System Kickstarter. The item comes in both painted and unpainted versions. The Sewer Wall Pack comes with these 27 pieces: (1) Grate, Removeable (2) Wall, Concave Curve (4) Wall, Convex Curve (1) Wall, Hole w/plug (Kickstarter counted the plug as a separate piece) (1) Wall, Ladder (8) Wall, Straight 1" (10) Wall, Straight 2"