For use with the Solar Charge Box https://www.youmagine.com/designs/solar-charge-box-v1Assembly instructions: - Print the two parts. - Use the velcro to mount the solar charge controller on to the bottom box. - Install the LED Volt meter in the volt meter printed box. - Install the push button switch in the volt meter printed box. - Solder the red (+) wire from the LED Volt meter to one terminal on the switch - Solder a red wire to the other terminal on the switch - Solder the other end of the red wire to the positive battery wire in the Charge Box unit. - Solder the black (-) wire from the LED Volt meter to the negative wire in the Charge Box unit (add extra wire as required). - Use the 4 screws to attached the LED volt meter box to the main charge controller box.  - Push the switch, the LED Volt meter will display the battery voltage..