Wheel blocks to prevent rolling of parked aircraft or tractor trailers.
A block of wood or rubber to stabilize the wheels when parking an aircraft.
Wooden stands on which the boats rest.
rock protection that is wedged into cracks by hand. Nuts is a synonym.
Wooden or metal blocks constructed to fit the curvature of a tire and placed against the tire to prevent apparatus rolling.
Wooden, wedge-shaped blocks placed in front of the wheels of the aeroplane to prevent it from moving when the engine is started