It allows you to buy a number of random craftable hats (you can pick/choose the number) which are worth 1.44 ref (may change during time) without the need of selecting them.
Trade Offer
Auto-Sell Hats
Automatically sell up to 100 of your eligible hats at once.
Don't worry: we won't take special items, including painted, low craft numbers, special levels, spells, killstreaks, etc.
Autosell Cards
Automatically sell up to 1,000 of your eligible cards at once.