aluminum
アルミニウム
acrylic
air
air conditioning
architecture
barbed
bend
bending
brick
building
buildings
construction
duct
ducts
engineering
grille
hood
house
industrial
industrial areas
industry
inline
large
metal
pipe
pipeline
pipelines
pipes
radiator grille
red
round
shiny
silver
sky
steam
steel
technical
technique
technology
vent
ventilated
ventilation
wall
wire