The item pictured is a 3WF-3A knapsack power sprayer, also known as a mist duster or mist blower.
It is a gasoline-powered, backpack-style sprayer used for agricultural and gardening applications.
The device is characterized by its speed and efficiency in applying liquid treatments or dust.
It is powered by a 2-stroke engine and typically has a tank capacity of around 20 liters.
The design is intended to reduce manual labor compared to traditional hand-operated sprayer