CARTRIDGE

PROBLEM TO BE SOLVED: To provide a low-cost cartridge that a user can discriminate easily the decision of validity/invalidity of a built-in erroneous erasure preventive plug when viewed from the side of the side wall of a case and problems such as an appearance defect or the like do not occur. SOLUTION: For example, circular printing parts 74, 174, 274 are provided in one display part 72 of display parts 70, 72 formed on the right and left of a projection 68 for operation on the surface of the outer side of the erroneous erasure preventive plug 62. The display by a color and others is printed showing that the cartridge is erasable/recordable visually to the printing part 74. The outer peripheral portion of printing parts 74, 174 is formed as a portion 76 having a different height from the printing parts 74, 174, and the printing parts 174 and 274 are formed in a different height from the display part 72.