Abstract: Many of those having diabetes take a combination of slow and fast acting types of insulin. It is important that different forms of medicament do not become confused and that the patient does not receive an incorrect medicament. In order to meet the appropriate standard, certain dimensional restrictions are placed upon the cartridge. A medicament cartridge that meets the requirements of this standard and permits more ready discrimination between medicament cartridges having different contents is provided. The medicament cartridge of the present invention is provided with an electrical element having specified electrical properties located on an external face of a displaceable plunger.