Cutex Brand 10 Quilting Machine Large Aluminum Bobbins with Center Notch for Winding 10 QUILTING MACHINE LARGE ALUMINUM BOBBINS WITH NOTCH Pack of 10 Aluminum Large Capacity M Size Bobbins for Quilting / Embroidery Machines. M size bobbins measure 1" in diameter and 3/8" thick. Aluminum bobbins are considered the Top-End "Luxury Bobbins". They offer less resistance which translates to less drag to the bobbin thread tension. These high quality bobbins will fit many Quilting / Embroidery / Sewing machines using large capacity bobbins including : Works with Tin Lizzie 18"LS & 26" Ashley, Queen Quilter 18", Handiquilter HQ Sixteen, Baby Lock Jewel 18", Pfaff Grand Quilter 18", Viking Mega Quilter 18" Machines & Frames.