機器
abstract
background
bearings
bolt
bolts
brown
chain
cogs
construction
corroded
detail
dirty
engine
equipment
factory
gears
grunge
industrial
industry
iron
isolated
machinery
macro
material
materials
mechanism
metal
metallic heap
nuts
old
oxidation
part
parts
pile
retro
rust
rusted
rusty
rusty metal parts
safety
scrap
screw
steel
technology
texture
vintage