Hello, I'm a misc solt expander !
What ! You don't know what i can do ?
Dude, seriously...
Ok so it's simple, imagine you have already one hat and two miscs and one taunt equiped for the scoot, and today is your birthday, you go talk to your mom and you say : hey, can i make some grandma's money on steam please ?
And she say : Yes.

At this moment you're really, happy. So you go on the TF2 market and you see a beautiful misc for the scoot... The Sign of the Wolf's School... So you buy it, but after you see you can't equip three miscs but you love the three, and you can't choose. And at this moment i've got the solution : you go on the market and with the rest of your money you buy my misc solt expander, you use it and if the three miscs are compatible you can equipe the three miscs and your hat and your taunt...
And AT this moment you're really happy and you say : thanks Valve ^^