This is a new and improved version of "Warm Tube Clock" - the open source Nixie Clock project. All project files (schematics, PCB & source code) are available for download on project page: http://www.elektronika.ba/800/warm-tube-clock-v2-nixie-clock/. The clock consists of two PCBs: Main Board, and Nixie Shield Board. This PCB sale contains three sub PCBs which you will need to cut apart and you get: Main Board, IN-14 Nixie Shield and IN-16 Nixie Shield! This allows you to choose which Nixie tubes to use: IN-14 or IN-16.