The AMS First Stage Feeder is specially designed to support the AMS for printing multiple colors and materials. Each AMS has 4 first stage feeders, and each first stage feeder has its own motor and gears to actively push the filament forward or wind it back to the spool. The first stage feeder has a sensor to detect filament. When a filament is inserted, the first stage feeder will pull the filament automatically. When a filament needs to be winded back, the first stage feeder will drive the AMS driving sleeve to rotate the spool for filament winding.