Which identifying feature is typical for press-formed products?

Press-formed products are typically created using sheets of metal, which is why this option is the correct choice. During the pressing process, a flat sheet of metal is placed into a die and then shaped into the desired form through the application of pressure. This process is commonly used in industries to produce parts and components, such as car body panels, appliances, and various consumer goods because it allows for quick, consistent, and efficient production of parts.

The other options do not accurately describe the typical characteristics of press-formed products. Irregular shapes can be produced through other manufacturing methods but aren't a defining feature of press-formed products, which often have regular, controlled shapes. Hollow cylinders, while they can be formed through specific press processes, are not representative of the broader category of press-formed products that mainly utilize sheets of metal. Lastly, large molds are more associated with casting and forming techniques, rather than the sheet metal processing characteristic of press forming.