Features:1. Suitable tetrafluoroethylene tube 4mm2. Use 1.75 mm Supplies3. 7075 aerospace quality aluminum alloy surface sandblasting oxidation.4. Equipped with two pneumatic fittings, the feed process more smoothly, you can make your extruder closer to the print head (reducing brushed remote feeding problems arising from this can to some extent), while the supplies can be placed in a more appropriate position, and not worry about other issues stuck supplies)Package Included:1 x 42 stepper motor holder1 x MK8 extrusion gear1 x 624 ZZ pillow2 x Delivery head1 x Hexagon wrench1 x Adjusting springs set1 x Assembly srews set