The machine adopts automatic lubrication system and the mechanisms of the needle-bar,thread tack up and feed dog are excellently improved by using the structural alloy steel,therefore the running noises and vibrations are minimized signifiacantly,that the machine is operated under the quiet and comfortable circumstances to increase the efficiency and the service life of the machine is prolinged also.The machine is recognized as a highily efficient and dreliable,ensures highly improved sewing performance,and easily adapts to changes of the sewing material. It is available for ligh and medium weight materials such as weaving and knitting fabrics. ﹣B &﹣H are available for heavy weight materials such as leather,synthetic leather and canvas.