Symbol Tubes Symbol tubes CD14 Rodan-Okaya CD14 top-view symbol tube GR-524 The GR-524 is an extremely rare symbol tube made by Rodan-Okaya. It shows the abbreviated days of the week in Kanji. GR-574 The GR-574 is an extremely rare nixie tube made by Rodan-Okaya of Japan. GR-707 The Rodan-Okaya GR-707. A small top-view nixie tube showing electrical symbols. Clearly intended for use in a multi-meter. This has the unusual feature of a side-nipple. The pin arrangement is also very unusual. GR-836 The Rodan-Okaya GR-836 is a large and extremely rare top-view 'nixie' tube. It has two Japanese symbols, which as far as I can tell mean 'power' and 'on'. GR-1485 The GR-1485 is a symbol tube made by Rodan-Okaya of Japan. It has the letters A through J GR-43091 The GR-43091 is a symbol tube made by Rodan-Okaya of Japan. It has the letters A through J Unknown 1 This is an unknown Rodan tube that just has the characters 'A' and 'R' in it. It uses the same envelope as the GR-201 ZM1041 The ZM1041 is a large Nixie tube that can display a plus and minus symbol. It has a red coating to improve contrast. This particular one was made by Mullard of the U.K.