A phase-locked loop circuit, a phase converter module thereof and a phase-locked controlling method are disclosed herein. The exhaust gas pipe has an upstream open end connected to the sound deadening device positioned at the upstream side of an exhaust gas discharging direction, and a downstream open end through which the exhaust gas is discharged to the atmosphere. Hence, by making the tension of the individual magnetic tapes uniform, productivity and product quality can be stabilized and improved and yield can also be improved. The components of the molding tool are subjected to low wear, and the molding tool is unsusceptible to contamination. The present invention further provides a diamond simulant with durability, hardness, and optical features closer to that of a genuine diamond that previously afforded by other diamond simulants, such as cubic zirconia. The suite of services offered by these servers may be wirelessly accessed from a client device.