X-Acto economical bulk packs of blades are incredibly useful to have in studios workshops frame shops classrooms and other workspaces where creatives are making precise cuts. Precision-crafted of the highest quality carbon. Blue oxidized finish for rust resistance. Designed to handle a variety of tasks in which accuracy and cutting ease are essential. Blade Type: Hobby Knife; Material(s): Carbon; Blade #: # 11; For Use With X-ACTO By Boston Hobby Knives.