Carton of 50 Grooved Top Bar/Grooved Bottom Bar Frames. 18% more wood in end bars ( Full 3/8" Thickness) Grooved bottom bar is stronger and easier to use. Foundation is placed in bottom bar groove and top bar groove. This frame works best with Perma-Dent or Rite Cell foundation Fits 6 5/8 inch hive bodies (Medium/ Honey Supers) Not assembled.