double-ended, one end plain, other end cross serrated, 5.0 mm wide ends, 7″ (17.5 cm) Bone File #12A is a highly versatile file that can be used in surgical procedures that require manipulation of bone. It is ideally suit for some forms of bone reshaping such as a jagged edge that could endanger the tissue areas around it. In procedures such as craniotomies in which delicate brain tissue is being handled this file aids in keeping the bony area around smooth and free of harmful points. Additionally this instrument is double ended with one end plain and the other cross serrated making it a multi functional file.