THREE sets of 2 pieces (each set is 2 laser-cut heavy chipboard pieces — a solid back and a front with a window cut out).
Use them separately or hinge them together (with paper tape, metal hinges, etc.) to make into one wider group.
The 2 shorter side panels are 5-3/4" tall (and the windows are approx. 1-3/4" wide x 2-3/4" tall); the taller center panel is 7" tall (with a window approx. 2-1/4" wide x 3-3/8" tall).
3 sets (6 pieces).
Note: Items cut from this heavy, light-grey chipboard burn easily so the laser-cutting process may leave charcoal residue behind. Save yourself a headache, and just wipe the cut edges of these items down with a dry paper towel before assembling or painting.