Features: 100% brand new and high quality Very convenient to use. This expansion board as a driver expansion board, can be used for engraving machines, 3D printers. With a total of four slots, can drive four A4988 stepper motor. Each road stepper motors only need two IO ports. In other words, six IO ports can be well managed three stepper motors. Upgrade version. easier operation for 3D Printer engraving machine drive expansion board. Package Includes: 1 PC x A4988 Driver CNC Shield Expansion Board ( Package does include A4988 Driver) Specifications: Item: A4988 Driver CNC Shield Expansion Board Fit for: for V3 Engraver 3D Printer Version: V3.0 Size: pls. see the pictures note: Package does include A4988 Driver. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you