Plastic profiles include a single material or multiple materials. Single material profiles utilize one extruder while multiple material profiles require more than one extruder to feed material into a central die. These processes can utilize single screw or twin-screw extruders. Single screw machines are focused on pelletized materials or applications requiring less true mixing. Twin-screw extruders are usually focused on powdered materials or where more intensive mixing is required. These extruders can be of a variety of sizes from a few pounds per hour of output up to thousands of pounds per hour output depending on the application.