Ladder chain used on player piano to connect roll motor and transmission.
Player Piano Vacuum Motor/Suction Box Complete Automation Kit w/Rewind & Shutoff
NOS Aeolian (1960's and later) Player Piano Wind Motor Slide Valve Pushrods
J. Chein Vintage Piano Lodeon Mechanical Player Piano - Motor runs -
Unrestored/Used Lester Player Piano Wind/Roll Motor
Antique Kimball Player Piano Motor
Player Piano Wind/Roll Motor Ladder Chain, about 4 Links/Inch - 42 per ft