Dolam LC-513 Dolam LC-513 nixie tube LC-531 The LC531 is a medium sized nixie tube made by Unitra-Dolam of Poland. It has two decimal points in addition to the numbers 0-9. LC-631 The LC-631 is a medium/large sized nixie tube made by Unitra-Dolam of Poland. It is pin-compatible with other medium/large tubes such as the ZM1042 and the Z5660M
