Features Full support for MACH3 and other computer software that enables parallel port control, ensuring seamless integration with a variety of applications. Separated USB power supply and peripheral power supply to enhance computer security, providing peace of mind during operation. Wide 12-24V peripheral voltage input with anti-reverse connection function, ensuring flexibility and safety in power supply usage. All input signals are isolated by optical coupling, allowing seamless connection to various functions such as emergency stop, tool setting, and limit switches. One-way relay output port, controlled by the P17 port, providing convenient control over the spindle switch for enhanced operational efficiency. Specification: Input voltage range: 12-24VDC Package weight: Approx. 335g/11.8oz Package list: 1 * Stepper Motor Interface Board 1 * USB Cable 1 * Parallel Port Cable Package List