Lots of high quality sewing thread comes on a long spool about the size of a tube of lip balm, it doesn't fit into a standard bobbin.

I solved the problem by loading the thread onto a sewing machine bobbin (the metal type about 3/8" thick and the diameter of a quarter) By bending the legs of a standard fly tiers bobbin I am able to use these smaller spools.

They are particulaly nice for my travel kit, as I can now fit 3-4 colors in the space it took for one standard spool.