I, too, have been using Thread Heaven for years. I never do hand sewing without it. With Thread Heaven on my thread, if I get a knot in the thread as I am sewing, the knot is easy to get out. Oh, when it gets low, I scoop the remainder out of the box, roll it into a ball, and run my thread through the ball until the ball is gone. I keep lots of Thread Heaven on hand as I never want to be without it.