From Team Fortress Wiki
The Idea Tube is a community-created miscellaneous item for the Engineer. It is a leather tube strapped to the Engineer's back which contains a rolled team-colored blueprint and a yellow ruler. It also sports a handle and a white Mann Co. logo printed on the lower end.
- The Idea Tube was added to the game.
- [Undocumented] The Idea Tube was added to the drop system.
- Added Pyromania cosmetic items to the Mann Co. Store