3D Printer Accessories Set meets most needs. Including CNC Shield V3.0, R3 Board, A4988 StepStick Stepper Motor Module. The 3D printer stepper motor shield V3 can be used as driver expansion board for engraving machines and 3D printers. It has in total 4 channel slots for A4988 stepper motor driver modules for driving 4 channel of stepper motors. Each channel of stepper motor only needs 2 IO ports, which means 8 IO ports is sufficient to manage 3 stepper motors. This shield can make quick work for managing stepper motors in your project. CNC Shield Board: 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); 2 x End stops for each axis (6 in total); Coolant enable; Uses removable A4988 or DRV8825 compatible stepper drivers; Compact design; Stepper Motors can be connected with 4 pin molex connectors or soldered in place; Please note that this is an unassembled kit and Basic soldering skills are needed. A4988 Stepper Motor Driver: Low RDS (On) Output; Automatic current decay mode detection / selection; Mix with slow current decay modes; Synchronous rectification for low power dissipation; Internal UVLO; Crossover-current protection; 3.3 and 5 V compatible logic supply; Thermal shutdown circuitry; Ground fault protection; Load short-circuit protection; Five selectable step modes: full, 1/2, 1/4, 1/8 and 1/16 R3 Board for : MCU: USB interface: ATmega16U2 Operating voltage: 5V Digital I/O pins: 14 (including 6 with PWM capability) Analog input pins: 6 I-I/O pin output current: 40mA max 3.3V output current: 150mA max Flash memory: 32kB (0.5kB used by bootloader- included) Static RAM (SRAM): 2kB EEPROM: 1kB Clock speed: 16MHz Colour: Picture color Material: PCB Package Contents: 1 * RAMPS 1.4 Controller 1 * CH340 Board 1 * RAMPS LCD 12864 6 * Endstop Mechanical Limit Switch With Cable 5 * A4988 Stepper Motor Driver 5 * Heatsink 1 * USB Cable 1 * Ltype adapter plate 2 * FC cable Only above package content, other products are not included. Note: Light and different displays may cause color of item in picture a little different from real thing. The measurement allowed error is +/- 1-3cm.