וְעָשִׂ֤יתָ מִכְסֶה֙ לָאֹ֔הֶל עֹרֹ֥ת אֵילִ֖ם מְאָדָּמִ֑ים וּמִכְסֵ֛ה עֹרֹ֥ת תְּחָשִׁ֖ים מִלְמָֽעְלָה׃ (פ)
And thou shalt make a covering for the tent of rams’skins dyed red and a covering of sealskins above.
Read kabbalistic (mystical) interpretation of Exodus 26:14: and classical mystical sources.