Si Youyou worked as a quilter with thickened palms for seven years in a labor protection canvas glove factory. Her hands were pressed by the thick material and her knuckles became enlarged. Zhou Yuanxing, the first love who said that "there is no way out if the factory is broken", now comes back to work as a buyer in suits and ties. The first time we met again, I used a vernier caliper to measure the 0.3 Mm error in her quilting density. In the dust workshop, the sewing thread got stuck, and the cotton layer shifted after washing, and quality inspection conflicts were about to break out - he thought her gloves were not "standard" enough, and she laughed at him for being just that. But when Zhou Yuanxing tore open the layer of his gloves to reveal the crooked stitches, Si Youyou discovered that he had been imitating her quilting gestures for the past seven years. The thickened canvas is used to resist bumps and bumps, and people are on guard to avoid getting hurt again. When the old quilting machine jammed the last stitch, they realized: if the thread is too tight, it will break, if it is too loose, it will fall apart, and the stitch length in life must be just enough to allow another pair of hands to reach in.