Models: BJ8810/BJ8820 Details: This machine has been equipped with a link take-up thread and dr Models: BJ8810/BJ8820 Details: This machine has been equipped with a link take-up thread and driving roller presser. The timing of the roller and needle feeds combined with the rotating vertical thread-catching hook form two lines of lock stitching. The upper and lower shafts are driven with precision by the 'Synchro' belt. The bottom stitch regulator and safety clutch prevent damage to the machine.