WIKI: http://wiki.keyestudio.com/index.php/Ks0095_Arduino_CNC_Kit_/_CNC_Shield_V3.0_%2Bkeyestudio_Uno_R3%2B4pcs_a4988_Driver_/_GRBL_Compatible

V3.0 Features

Latest Arduino CNC Shield Version 3.0
GRBL 0.8c compatible. (Open source firmware that runs on an Arduino UNO that turns G-code commands into stepper signals)
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)
Spindle enable and direction
Coolant enable
Uses removable Pololu A4988 compatible stepper drivers. (A4988, DRV8825 and others)
Jumpers to set the Micro-Stepping for the stepper drivers. (Some drivers like the DRV8825 can do
up to 1/32 micro-stepping )
Compact design.
Stepper Motors can be connected with 4 pin molex connectors or soldered in place.
Runs on 12-36V DC. (At the moment only the Pololu DRV8825 drivers can handle up to 36V so please consider the operation voltage when powering the board.)

Kit List

1x CNC Shield V3.0
1x keyestudio uno R3 board
4x A4988 driver
1x USB cable