From the Super Mario Wiki
Filament MTMSNES.png Filament MTMDX.png
SNES (left) and PC (right)

First appearance

Mario's Time Machine (1993)

The Filament is an item in the SNES and PC releases of Mario's Time Machine. It is a thin strip of carbonized bamboo that Thomas Edison used to complete his incandescent light bulb in 1879. Mario takes it from Bowser's Museum after Bowser travels back in time and steals it from Menlo Park. He then travels back in time himself and shows it to Menlo Park's inhabitants in an attempt to find out who it belongs to. The druggist mentions that Edison is likely the only person in the area interested in such an item, though Mario can only return it after absolutely confirming it (which includes reading a Telegram that says that using this Filament can potentially lead to innovations such as power plants and motions pictures). Mario gives it to Edison in his workshop, and he immediately uses it to successfully power his new invention.