For heavy-duty projects, the Gore® Tenara® M1000H-5 Size 138 in white provides extra seam strength with its thicker ePTFE fibers, built to resist UV exposure, mildew, and corrosive cleaners formula-free. The bright white tone keeps stitches looking clean and seamless—even after repeated cleaning and sun cycles. This heavyweight original style thread ensures serious reinforcing power without sacrificing the lifetime durability Tenara is known for. It’s the go-to for demanding applications where lasting craftsmanship matters first.