To bevel the gingival margin of a tooth during cavity preparation.Margin Trimmer N. 26 (Black’s Formula: 13-95-8-14), Distal Cavity preparation margin trimmers are used with a lateral scraping motion.The blade of the instrument must be always kept parallel to the cavity wall to remove unsupported enamel rods or roughness. FILLING INSTRUMENT OT4 FILLING INSTRUMENT OT4