The Samsung/SAM4s SER-6500-II uses 44mm bond paper rolls and an ERC-18 ink ribbon cartridge. Because this register model was made before thermal paper came into wide use it uses the bond or impact 44mm paper. This register's printer is a dot matrix printer which of course is why it uses an ink ribbon of course.. Always keep paper in both the receipt and journal printers as operating without paper can damage the printer. Keep a fresh ribbon in the register and never use a re-inked ribbon, use only factory inked and sealed ribbons.