The Janome HD9 Black Edition and the HD9 Version 2 take a new version of the Large Jumbo Metal Bobbin. This Jumbo Metal Bobbin holds 40% more thread than traditional L sized bobbins. More thread on the bobbin allows you to keep sewing longer without interruption. This is extremely useful while performing high speed stitching. Keep a few on hand so that you can wind a new bobbin using the independent bobbin winder on the machine so that you always have a full back up on hand for when you do finally run out. The current Version 1 Parts and the new Version 2 parts are not compatible