CNC Shield Board Version 3 0Color RedSize L W H 68 x 53 x 18 mmVoltage DC 12 36 V At the moment only the DRV8825 drivers can handle up to 36V so please consider the operation voltage when powering the board Features 1 Uses removable A4988 or DRV8825 compatible stepper drivers 2 The extension board can be used for carving machine 3 d printer driver expansion board3 GRBL 0 8 compatible Open source firmware that runs on an UNO that turns G code commands into stepper signals 4 PWM Spindle and direction pins 4 Axis support X Y Z A Can duplicate X Y Z or do a full 4th axis with custom firmware using pins D12 and D13 5 Compact design Stepper Motors can be connected with 4 pin molex connectors or soldered in place 6 Please note that this is an unassembled kit and Basic soldering skills are needed A4988 Stepper Motor Driver Color RedSize L W H 20 x 15 x 10 mmThermal shutdown circuitry YesCrossover current protection YesGround fault protection YesLoad short circuit protection YesCompatible logic supply 3 3V and 5 VFive selectable step modes full 1 2 1 4 1 8 and 1 16Features 1 Mix with slow current decay modes 2 Internal UVLO and Low RD5 On Output 3 Automatic current decay mode detection selection 4 Synchronous rectification for low power dissipation 5 Warning Connecting or disconnecting a stepper motor while the driver is powered can destroy the driver Uno R3 Board MCU ATmega328Clock speed 16 MHzUSB interface ATmega16U2Operating voltage 5