Exodus 36:27

He made forty sockets of silver under the twenty boards: two sockets under one board for its two tenons, and two sockets under another board for its two tenons.

For the second side of the tabernacle, on the north side, he made twenty boards

and their forty sockets of silver: two sockets under one board, and two sockets under another board.

He made two boards for the corners of the tabernacle in the far part.

They were double beneath, and in the same way they were all the way to its top to one ring. He did this to both of them in the two corners.

There were eight boards and their sockets of silver, sixteen sockets—under every board two sockets.