These bobbins are 50wt Masterpiece 100% cotton, 2-ply thread and hold 80 yards of thead.

Remember that this same thread on the spool is 3-ply and not suitable for hand sewing like appliqué —only the bobbins are 2-ply.

These are the 16 colors Superior has chosen to continue producing (for now). New Efina bobbins from Wonderfil can be found here. Between Efina and Masterpiece there are 30 useful colors for hand appliqué.