1：Manual control: manually adjust the position of the three axes of XYZ as the starting point of carving, manually open or close the spindle.
2：Document engraving: the offline board can be linked to the GRBL control board for carving without storing a computer.
3：Storage file: After the offline board is connected to the computer, it is recognized as a USB mass storage device, and the engraving file can be directly accessed. More at https://www.brandreviewly.com/best-cnc-milling-machine/.
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