a close up photo taken on a construction tractor hydraulics assemble

yellow paint painted hydraulic hydraulics pneumatic pneumatics air fluid control controls actuate actuator actuators lift lifting compressible incompressible force cylinder cylinders extend retract extending retracting power heavy duty horsepower powerful torque close closeup partial view parts construction site sites vehicles vehicle equipment tractor tractors track tracks tracked wheel wheels dig digging terrain mud muddy soil earth excavator excavators skid steer steers crane cranes backhoe bulldozer bulldozers dump truck trucks concrete cement mixer mixing compactor compactors labor labour industrial