From TF2 Wiki
The majority of items in Team Fortress 2 have an associated Item level. This level is purely cosmetic and can be anywhere between 0 and 100 inclusive. Different types of items will have different levels, with items considered more "rare" usually having a higher level. At one point, dropped weapons were given a random level, but that was removed in a patch. So far, there are seven different types of items:
- Normal weapons are all level 1, which can be observed in-game by clicking the box labeled 'Show Stock Items' located in the
- or weapons are usually level 1, 5, 7, 8, 10 and 15, though there is no difference between levels.
- Most are given a random level from 0-100. Although there are a few special exceptions to this. For instance, many of the promotional event hats such as , the and the all have the same level of 10.
- All are level 50.
- All are level 100.
- All s are level 100
- All promotional/special event are level 5, 10, 15 or 20, with the higher levels associated with more prestigious badges.
- Whereas the Spy's , the Pyro's and the Medic's all retain the random 0 - 100 levels.