i do not know of it found this link on it pretty expensive to me it says brother machune but i know my brother only likes brother bobbin thread

I have used The Bottom Line many times--nice to have colored bobbin thread--especially for towels and items that the back shows. But for FSL, I use embroidery thread needle and bobbin and the design is more balanced with equal weight thread. Poly is my thread of choice for FSL--it gives a crisper finish. I order Madeira PolyNeon in the 5000 meter cones. Lj