The manual & electric knapsack sprayer is the latest innovation in the world of agricultural spraying. This sprayer not only has advantages in spraying liquid storage capacity, but is also equipped with a dual operating system that makes it easier for users to apply pesticide or fertilizer liquid. One of its outstanding features is the ability to be operated in two different ways. First, users can easily activate spraying by simply pressing the ON button located on the body of the sprayer. This allows the user to spray the liquid automatically with a single press, allowing for convenience and efficiency in use. Secondly, users can also spray using the sprayer’s pump system.