A piston filler is a type of filling machine commonly used in the food, cosmetic, and pharmaceutical industries. It operates by using a piston to draw liquid into a chamber and then dispense it into containers. This method allows for precise control over the volume of liquid being filled, making it ideal for products that require accuracy. These machines can handle a variety of viscosities, from thin liquids to thicker pastes. They are often used for filling products like sauces, creams, and oils. Piston fillers can be manual or automated, depending on the production needs of a business.