The Valve quality is assigned to certain items owned by Valve employees. In some cases, they possess the Flying Bits particle effect. Because of their nature as developer items, they may possess ridiculous item attributes, as seen in the backpack example; however, these additional attributes are not part of the Valve quality itself. Some Valve quality items may be completely identical to a Normal or Unique quality weapon aside from the name.
The plethora of buffs on some Valve weapons are, on rare occasions, used by Valve employees for entertainment.
The hexadecimal color code for Valve items is.
Robin Walker going on a rampage with his Valve Rocket Launcher in a public server:
Another video of Robin Walker with his Valve Eyelander
Flying bits attached to the Escape Plan.