機器
abandoned
abstract
architecture
background
black
bolts
brown
circle
circular
cistern
closeup
communications
connection
construction
course
crusty
curved
derelict
design
frame
grainy
grunge
grungy
hole
industrial
industry
iron
junk
marine
material
metal
metallic
metallurgy
object
old
porthole
rough
round
ruined
rust
rusty
screws
shell
ship
steel
tank
texture
tube
window