If your old controller is RDC6442 and the keypad is worn out, you can use this panel to replace. Ruida RDC6442G/S system is a new generation system for 4-Axis control of laser engraving and cutting. Digital Laser Control Signals: (1) TTL level output, 50 mA, Drive Capability (2) PWM frequency 2K-50K for adjustable (3) PWM duty ratio is 1% 99%, adjustable (4) PWM value is up to 5.0 V One-Way 24V Power Supply, >2A Motor Control Signal: Common-anode Output, Drive Capability 20 mA. Motor control pulse frequency: Max.