From Team Fortress Wiki
The K-9 Mane is a promotional headwear item for the Demoman and Heavy. It appears as a team-colored wolf head draped on the player's head. When worn by the Demoman, the K-9 Mane will have a scarred left eye.
Main article: Paint Can
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- The K-9 Mane was added to the game.
- [Undocumented] The K-9 Mane is now tradable and added to the Mann Co. Store.
- The K-9 Mane is now paintable.
- [Undocumented] Updated K-9 Mane item type to "Spirit Animal".
- The K-9 Mane was originally intended to be used as a promo for the Warpath Campaign DLC for Empire: Total War. 
- The term "K-9" is usually used to refer to police dogs, as it is a homophone of "canine".