Exodus 26:17-19

Revised Standard Version

¹⁷ There shall be two tenons in each frame, for fitting together; so shall you do for all the frames of the tabernacle. ¹⁸ You shall make the frames for the tabernacle: twenty frames for the south side; ¹⁹ and forty bases of silver you shall make under the twenty frames, two bases under one frame for its two tenons, and two bases under another frame for its two tenons;