grab bag

noun5

1. •
   A gift, purchase, etc. whose contents are concealed until after a selection is made; a bag as gift that comprises mystery prizes.

   • Winners can choose a gift from the grab bags on the table.
2. •
   A bag from which a gift or prize may be withdrawn (grabbed) unseen.
3. •
   (figurative) Any random assortment, selection or possibility.

   • With that system, it's a grab bag which files we can find at any moment.
4. •
   A moderately large bag of crisps or other snack, suitable for sharing.
5. •
   A bag containing essential items, which can be easily picked up and taken in an emergency.