Lobular design drive reduces stripping damage by driving fasteners on flats instead of forcing the corners. For use with sheet metal screws and other hexagonal head fasteners. No. 3548121C: 1/4" x 2-9/16" No. 3548321C: 5/16" x 2-9/16" No. 3548521C: 3/8" x 2-9/16"
