Twine shifters that enable the mechanical knotter of a hay baler to tie either two twines into a 2-twine knot or tie four twines into a 4-twine knot. For a 2-twine knot the twine shifters each move their respective upper and lower twines out of the needle's path where the twines are gathered to be tied in a knot. So when the needle swings through its path it only picks up two strands, and misses the two strands moved out of its path. To tie a 4-twine knot the upper and lower twine shifters each move their respective upper and lower twines back into the needle's path. This allows the needle to gather up all four twine strands to tie in a 4-twine knot.
