Seat belt textile or similar poliester fabrics should be cut smoothly but the problem starts at the cutting point. At the cutting point, very small fabrics can go out from the textile. Ultrasonic cutting method, cuts and seals at the same time so there is no small fabrics at the cutting point. Another method is by heating knife but this time the cutting point becomes very hard, not soft. So when the user touches it, it can damage hand. After Ultrasonic cut and seal process, the edges are soft and there is no short fabrics, all of them are sealed.