機器
agriculture
antique
background
beam
bearing
black
detail
diesel
dirty
engineering
equipment
exhaust
farm
heavy
historical
industrial
industry
iron
lens
light
machinery
mechanic
metal
obsolete
oil
old
part
physics
pipes
power
powertrain
pump
reflector
repair
retro
rural
rusty
steampunk
steel
system
technical
technology
tractor
transportation
truck
vehicle
vintage
wheel
work