Knot Making technique:
The knot will not come undone while the remainder of the thread is pulled with great force - as is needed in stitching the edges of the mattress. And what's really amazing is that the knot can actually be untied very easily by pulling the loops. This allows the beginning and the end of the thread to be tied together creating a continuous line of stitch around the top of the mattress - or form. The thread is a thick polyester.