Exodus 26:17 KJV
Two tenons shall there be in one board, set in order one against another: thus shalt thou make for all the boards of the tabernacle.
Exodus 26:17, King James Version
In context
16 Ten cubits shall be the length of a board, and a cubit and a half shall be the breadth of one board.
17 Two tenons shall there be in one board, set in order one against another: thus shalt thou make for all the boards of the tabernacle.
18 And thou shalt make the boards for the tabernacle, twenty boards on the south side southward.