Hi Phil: In the good old days, these drop actions without bridle straps had a felted rail behind the jacks which prevented the jacks from getting jambed up underneath the butt felts when reinstalling. Also for the spinet versions, it was helpful as someone else mentioned to have a rod to hold the backchecks up especially for the treble section where there were no damper spoons to keep the wippens from dropping too far. Jim Coleman, Sr.
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