Exodus 39:9

Overview - Exodus 39
1	The cloths of service and holy garments.
2	The ephod.
8	The breast-plate.
22	The robe of the ephod.
27	The coats, mitre, and girdle of fine linen.
30	The plate of the holy crown.
32	All is finished, reviewed, and approved by Moses.

Exodus 39:9  (King James Version)
It was foursquare; they made the breastplate double: a span was the length thereof, and a span the breadth thereof, being doubled.