Usually, I have associated lamps with the “GE-Hitachi” branding as lamps intended for the Japanese market.
Judging by the information provided, it seems likely that it could be one of those Japanese 1 meter (39 inch) FL35SS tubes.
Shown below are the specifications for one of these tubes:
https://www.hotalux.com/se/at_file/06116363/teikaku_FL35SSEXDHG_1.pdfIt seems like they are rated for 34W operation. If you do show us a photo, I can help you with finding more information. In that case, I recommend posting in the “gallery” since most lamp photos belong there.