Features: Support 4-axis linkage, you can connect four stepper motor drives or servo drives. The maximum step pulse frequency is 100KHz, which is suitable for servo motor or stepper motor. Support automatic probe tool. Emergency input support. Limit switch support. Support for connecting electronic hand wheel. Need to use external 24V DC power supply to isolate USB and external port and make the system more stable. Have 0-10V output port, you can use MACH3 software to control spindle motor speed. 4 general purpose inputs, you can connect limit switch, estop switch, probe switch, return to zero and other device. 4 general-purpose isolated relay drive output interface, can drive four relays to control spindle starts, forward rotation and reverse rotation, pumps and other devices. Status LED, indicates the connection status on the board. Specifications: Size: approx. 8 x 7.7cm / 3.15 x 3.03in Weight: 160g Package Included: 1 x USB CNC Controller Board 1 x USB Cable 1 x CD Note: Please note that the new type and old type of this product will be sent randomly and please make sure you will not mind before ordering.