Studious. The sewing machine in clothing factory is an electric machine, which can be used flexibly after a period of use, and the sewing speed is faster than that of household sewing machines. The phoenix eye, button door and flat eye are commonly known as "buttonholes", and the phoenix eye is usually used for I-buttons (jeans) or larger buttons on coats. A flat eye refers to a hole with the same width at both ends, usually a flat eye on a man's shirt.