Aluminum Bobbins Juki Dnu-1541-7, Ls-341n Sewing Machine - 3 Pk #D9117-141-e00 Pack of 3 Original Juki Aluminum Bobbins For Juki Industrial Sewing Machines. Juki part # D9117-141-E00 Large capacity M size bobbins. Bobbin size : 1" diameter X 3/8" thick (25.5mm X 10mm) Genuine Juki part.