Descriptions: The control arm for wire feeding is more accurate for remote extrusion and back drawing. Lower requirement for torque of extrusion stepper motor, which reduces the probability of failure during back pumping, plugging and refueling. Compatible with more types of consumables, such as flexible TPU. Easy to refuel. You can choose short or long distance extrusions at any time, which is easy to remove. Because it is a kit, it does not affect the original functions of your printer. Specification: .