One of the web forming methods in nonwovens is called dry laid. The primary machine used to form a web in the dry laid process is a roller top card. The primary purpose of a card is to open tufts of fiber presented to it from a fiber feeding system that is usually comprised of several open-ing hoppers, a blending reserve, a fine opener, and a chute feeding the card. The card has many rolls in it that are covered with metallic teeth. These teeth convey and open the fibers as the rolls turn. Especially important in a roller top card is the interaction of the worker and stripper rolls with the main cylinder. The majority of carding of the fibers takes place between the workers and strippers. There are usually 3 or more sets of workers and strippers around the main cylinder. The main cylinder carries the fibers through the card. When the fibers exit the card, they have been combed by the card so that the fibers are parallel. The card also blends fibers as they are processed.