Shemot 36:21-23

Orthodox Jewish Bible

²¹ The length of a keresh (plank) was ten cubits, and the width of a keresh one cubit and a half.

²² One keresh had two yadot (projections, tenons), equally distant one from another; thus did he make for all the kerashim of the Mishkan.

²³ And he made kerashim (frames) for the Mishkan; twenty kerashim for the negev (south) side southward;