Which two characteristics are associated with flats?

The choice of flexible and uniform thickness aligns with the characteristics of flats because flats are typically defined as lightweight mail pieces that are larger than letters but smaller than packages. They have a consistent thickness across the item, which facilitates their handling and processing within the postal system. This uniformity is crucial for efficient sorting and delivery through automation, as it allows machines to easily recognize and handle these items.

Flats tend to be made from materials that allow for some flexibility, such as paper, cardboard, or other lightweight materials, which can withstand the rigors of mail handling without becoming damaged. This flexibility gives them an advantage in being able to fit into sorting machines and delivery routes effectively. The standardization of thickness ensures that they can be processed through the systems designed specifically for flats, making this characteristic essential to identifying them correctly within postal operations.