... embroidery back fabric more spun Polyester thread embroidery machine Bottom ThreadUnder ThreadBack Thread for pre woundis made of texturized ... leather products,main used for embroidery machine2) Thread Weight: Approx 675g/bobbin Bobbin Weight:35g Colors: White, Black,Red,Green ... packing also 100% spun polyester 30S embroidery machine bottom thread/under thread/back thread bobbin thread for pre wound