Hand-tied wefts are hair sewn or tied together meticulously by hand using a strong piece of weaving thread. If they’re done properly, hand-tied wefts can actually last a very long time.
Machine wefts are sewn together using a sewing machine. Machine wefts are slightly thicker compared to hand-tied wefts, but a bulge is rarely noticeable. A lot of people prefer machine wefts because the tracks can be cut during installation, making it a bit more flexible.