A typical automotive exhaust resonator is made of a hollow steel cylindrical tube and is attached to the muffler of an exhaust system. This type of resonator is designed similar to that of an acoustic resonator, which creates an âexhaust noteâ that gives the exhaust noise a less annoying and more pleasant tone.The sound can be enhanced by means of adjusting the exhaust note. typical automotive exhaust resonator is made of a hollow steel cylindrical tube and is attached to the muffler of an exhaust system. This type of resonator is designed similar to that of an acoustic resonator, which creates an âexhaust noteâ that gives the exhaust noise a less annoying and more pleasant tone.
buttonhole (plural buttonholes) 1  A hole through which a button is pushed to secure a garment or some part of one. ( 2 chiefly Britain) a flower worn in a buttonhole for decoration.
Prior to the existence of the zipper, buttons were the most common back closure found on women's clothes. in the past, a dress was usually made with buttons covering the back from the neck down the waist, or several inches below. A blouse contained buttons down its full back. But later in the 20th century, garments for women were made with fewer buttons. Toward the end of the 20th century, the keyhole button closure became popular on dresses and blouses made of nylon or silk, popular fabrics at the time.