Exodus 26:5

26:5 You shall make fifty loops in the one curtain, and you shall make fifty loops in the edge of the curtain that is in the second coupling. The loops shall be opposite one to another.
-World English Bible

Other Translation

26:5 Fifty loops shalt thou make in the one curtain, and fifty loops shalt thou make in the edge of the curtain that [is] in the coupling of the second; that the loops may take hold one of another.
-King James Version