All distal surfaces of bicuspids and molars. Terminal shank reach is 7 mm. NORDENT Rigid Gracey Curettes feature a rigid shank and a longer reach blade and are well-suited to periodontal and surgical application. NORDENT Rigid Gracey Curettes have a 1.3 mm terminal shank diameter and blades that are 0.9 mm wide and 6 mm long. Featuring our DuraLite Hex Handle, additional handle options are shown below.