The Two Row Bobbin tunnel is simply the best bobbin organizer available today.  Your bobbins simply snap in place!  The bobbin thread is held firmly in place  on your bobbin as you store it away in the bobbin tunnel..  We have filled the Bobbin Tunnel with 40 131 yards White  continuous polyester thread prewound bobbins. Parallel wind for smoother running. No fuzz lint or wax buildup like paper bobbins. No distorted flanges from from humidity or oil. No jerks or jamming from distorted flanges. Clear plastic to see amount of thread left.