It comes with a power cable and a D-sub 9-pin male to D-sub 9-pin male cable. So you are ready to test your laser after you connect your Thorlabs 14-pin laser mount (see htm link below). Line voltage: 115 VAC . You can change to 230 VAC according to the procedure of page 4-1 of last pdf link below. Sample 1 is with original knob, as shown at the right of 2nd photo below. Sample 2 is with third-party knob. GENERAL DESCRIPTION The LDC 500 laser diode controller by Thorlabs is an extremely precise controller for laser diodes and LEDs. When used with the Thorlabs TEC2000 temperature controller, the laser current or the optical output power and the temperature of the connected laser diode can be precisely regulated. Thus the laser diode works as a stable optical transmitter. The LDC 500 laser diode controller is well suited for: - Safe and simple operation of all laser diodes up to 0.5A - Power stabilized light sources - Wavelength tuning by controlling the current - Wavelength modulation by current modulation To protect the laser diode against damage, the LDC 500 provides the following protection circuitry: - Softstart function- Adjustable laser current limit - Safety Interlock (open circuit monitoring of the laser diode mount connection) - Electronic short-circuit for the laser diode - Separate enable switch to turn the laser diode current on and off - Monitoring LED for LASER ON mode Features: • The LDC 500’s front panel arrangement makes it easy to use. • The operating levels (laser current, current limit, laser power, photodiode current), selected via a push button switch, are shown on an illuminated 4½-digit LCD display. • The on/off delay and the soft start function protect the laser diode against undesired spikes. • An independent limit for the laser current can be set with a 20-turn potentiometer, protecting the laser diode from operating errors. • When the output is open, an electronic switch short-circuits the current output and no voltage is applied to the laser diode .……