Machine in your image is a gas-powered vibrating concrete screed (specifically a Vibro Letva), used for leveling and compacting freshly poured concrete. It uses high-frequency vibrations to eliminate air pockets, ensuring a denser and more durable finish. [1, 2]
Key Components
4-Stroke Engine: Typically a 1.2HP to 1.5HP gasoline motor (often GX35 style) that provides smooth power with low fuel consumption. Unlike 2-stroke engines, this uses straight gasoline and has a separate oil reservoir.
Vibration Module: Houses eccentric weights that generate the oscillation needed to settle the concrete.
Damping System: Heavy rubber mounts between the motor and the handles to reduce vibration felt by the operator.