vent is part of:

vent contains:

Full expansion for vent:
   100%  1x4 Tile w/ Parallel Black/Gray Lines
   100%  2x2 Sloped Brick w/ 7 Black Lines
   100%  2x2 Tile w/ 7 Black Parallel Lines
    80%  2x3x6 Convex Corridor Side w/ 5 Bars