Amecotex&reg; - 144-Pack 75D/2 Plastic Prewound Style SA156 / 15J (PWB250) Sewing Embroidery Bobbins For Brother, Singer, Janome and Babylock Embroidery Machines (Black) Size "A", Style 15, 130 Meter (143 yards) Plastic sided provides uniform tension. High yield fiber equals more stitches per bobbin It is wound on a plastic sided bobbin shell. Because of this, it is not affected by humidity or oils. It is responsive to machine thread sensors so you dont have to worry about your yardage. 100% Polyester Filament Bobbin Thread, Style SA156 / 15J (PWB250) Bobbins will fit all Janome home embroidery and sewing machines as well as most Singer embroidery machines.