Safety belts are more than just straps that drivers and passengers wrap around their bodies. Rein fact, seat belts today are called three-point. They have a single continuous length of webbing. Use a heavy-duty machine for thick fabrics. Load your machine with thread that is suitable for seat belts. Done! https://bladt-ulriksen.federatedjournals.com/the-federal-motor-vehicle-safety-standard-seat-belt-webbing-diaries