Exodus 26:23-27

And two boards shalt thou make for the corners of the tabernacle in the two sides.

And they shall be coupled together beneath, and they shall be coupled together above the head of it unto one ring: thus shall it be for them both; they shall be for the two corners.

And they shall be eight boards, and their sockets of silver, sixteen sockets; two sockets under one board, and two sockets under another board.

And thou shalt make bars of shittim wood; five for the boards of the one side of the tabernacle,

And five bars for the boards of the other side of the tabernacle, and five bars for the boards of the side of the tabernacle, for the two sides westward.