Coupling

kup'ling: Is the FV rendering of machbereth. This Hebrew word means joining, or the place where one thing is joined to another, as of the curtains of the tabernacle (Ex 26:4-5), and of the different parts of the ephod (Ex 28:27; 39:20).

⇒See the definition of coupling in the KJV Dictionary

It is also the English Versions of the Bible rendering of mechabberoth, and this refers more to the thing that joins the two objects, as beams of wood (2Ch 34:11), or hooks of iron (1Ch 22:3).

⇒See also the McClintock and Strong Biblical Cyclopedia.