The JZDS-2 Electronic Yarn Storage Feeder has been designed for the feeding of yarn at constant feed rates. Compared to the feeder apply to flat and sock machine, this type applied to jacquard circular knit machine has equipped with top yarn income device and bottom yarn output sensor. The feeder is driven by a powerful brushless DC motor. It can automatically storage yarn according to yarn demand of the knit machine and keep yarn separation while feeding the yarn smoothly.