I always have bobbins with trailing threads in my machines compartments. I have tried the elastic hair pieces and not only do they not really work, I can't see the color of the thread. I love the bobbin boats. The bobbin stays put and no thread trails and I can see the color plus the length is right to fit right in my machines compartments. I have looked at the round bobbin holders but then I would have to store them somewhere else. The size is right. Love them!!