I don't know where they got the small box size, but it's definitely NOT 2-1/2 inches wide. The opening for small drawers is only 2-3 inches. 16 inches wide, a full 5/16 inches smaller. The boxes themselves are about 2-1/8 inches wide from outside to outside. Small drawer interior dimensions are 2-1/32" wide x 5-3/8" long x 1-3/8" deep. Large drawer interior dimensions are 4-5/16" wide, 5-3 /8" long, 2-1/4" deep.