Exodus 28:16

28:16 It is to be square when doubled, nine inches long and nine inches wide.

Exodus 30:2

30:2 Its length is to be a foot and a half and its width a foot and a half; it will be square. Its height is to be three feet, with its horns of one piece with it.

Exodus 39:9

39:9 It was square – they made the breastpiece doubled, nine inches long and nine inches wide when doubled.