YLI Wonder Invisible Thread-Clear
YLI Wonder Monofilament Thread
The manufacturer says: "The top thread for machine quilting .004 1500 yd / 1375 m. The very finest monofilament thread available. Use in the bobbin and needle for a really blind hem. Can be used in sergers or conventional machines."
Londa says: "My favorite monofilament thread - nylon. Cross-wound spool so can use it both on horizontal and vertical thread delivery spindles. 1500 yards. VERY fine at .004
Select Clear for light colors - Smoke for dark colors.
I use for couching yarns at 3.0 long and just wide enough to go over the yarn. I use only in the needle, and lower the upper tension however much is needed so that I don't see the regular thread in the bobbin peaking at each side of the zigzag."