An ink jet printing member mounted on a scanning carriage to discharge ink for recording while traveling with the carriage includes an extrusion that engages with a hook of the scanning carriage when this member is mounted on the carriage. This extrusion is arranged to dually function to identify the kind of the mounted ink jet printing member in accordance with the location of the extrusion and to secure the printing member on the carriage. With this arrangement, the structure is simplified to reduce the manufacturing costs significantly, while preventing the user from erroneously mounting an ink jet recording member on the carriage for an intended recording.