The 6 1/2" Lockhart Mummery Fistula instrument, slightly curled, is a specialized surgical tool used in the treatment of fistulas, particularly in procedures related to the ear, nose, and throat (ENT). The "6 1/2" refers to the length of the instrument, which offers a good balance of reach and control during surgery. The "slightly curled" design allows for better maneuverability when working in tight or difficult-to-access areas, helping the surgeon to accurately identify and treat fistulas.