Drum cartridge including electrical contact surface positioned at outer surface of drum frame

A set of cartridges each detachably attachable to a frame of an image forming apparatus, the set of cartridges comprising:

• a drum cartridge comprising;
• a photosensitive drum rotatable about a first axis extending in a first direction;
• a drum frame having one end portion and another end portion spaced apart from the one end portion in a second direction, the photosensitive drum being positioned at the one end portion of the drum frame in the second direction;
• and
• a first storage medium including a first electrical contact surface;
• and
• a developing cartridge comprising a second storage medium including a second electrical contact surface,
• wherein the drum frame comprises:
• a first drum side plate;
• a second drum side plate spaced apart from the first drum side plate in the first direction, the photosensitive drum being positioned between the first drum side plate and the second drum side plate in the first direction;
• and
• a first connecting plate connecting the first drum side plate and the second drum side plate, the first connecting plate being positioned at the another end portion of the drum frame in the second direction, and
• wherein the first electrical contact surface is positioned at an outer surface of the first connecting plate.