Knife refill cartridge is designed for use in GP Pro Ultra SmartStock Tri-Tower Cutlery Dispenser. Pre-counted, pre-assembled refill makes it fast and easy to restock an empty dispenser. Simply pick up a new Series-T cutlery refill, slide it into the dispenser, grasp the pull tab, pull away the paper band and close the door. Knives are made of polystyrene plastic.