This is the thread I use for invisible machine applique. I don't care for most invisible threads because they're stiff, scratchy, and will melt if you touch them with an iron. That's not the case with monopoly thread. It's soft and flexible and I can iron my applique blocks like I would a hand appliqued block.

100 wt. monofilament polyester thread. Designed for invisible applique and quilting. This reduced-sheen monofilament polyester is the best choice when it comes to invisible threads. Unlike other monofilament threads made from nylon, MonoPoly is 100% polyester. Commonly referred to as an invisible thread due to its fineness and reduced sheen, MonoPoly is great for the bobbin or top.

Available in two colors, Smoke (for dark fabrics) and Clear (for light fabrics). This product has manufacturer advertised price restrictions. The SS price will come up in your cart.