https://everything2.com/user/vivid/writeups/flat%20fell%20seam
flat fell seam (thing)
A type of seam commonly used for the inseams of jeans, and in the construction of tarps and tents and shade pavillions. It is much stronger than your...
flat fell seamthing
https://www.merriam-webster.com/dictionary/flat-fell%20seam
FLAT-FELL SEAM Definition & Meaning - Merriam-Webster
The meaning of FLAT-FELL SEAM is a strong seam with two lines of stitching showing on the right side that is produced by folding one raw edge under the other...
flat fell seamdefinitionmeaningmerriamwebster