One. From the technical details of ultra-low tension fine suture, we can know that one layer is usually stitched, and if the skin is not well matched, another layer is stitched with absorbable internal suture. Ultra-low tension fine suture is to make a far positioning point in the dermis and then sew it deeply with suture. Pay attention to the position and level of needle entry, the route of thread in the tissue, the position and level of needle exit, the tightness of the knot, the needle distance and the edge.