Yes, the blue dot bobbin case came out before the 12000. It was brought out about the time the Horizon 7700 was launched, if my memory serves me correct. It can be used quite safely in your 12000, 15000, Skyline series and the other quilting machines that have a threader cutter. Jim, if I’m wrong will you please correct me. The blue dot bobbin case has a lower tension which is better for quilting, the yellow dot that comes with embroidery machines starting at the 12000 is for embroidery as it is a great tension to pull the needle thread under the embroidery to eliminate the bobbin thread from showing on top; then there is the red dot which is the standard bobbin case. The red dot, standard bobbin case sometimes works for everything - you need to test your sewing to see what works best for you. I think that the blue dot bobbin case is not included with all machines, so it may not have come with your machine, but you can purchase it from your dealer.
Cheryl - Saskatoon