Bag Of Holding

This bag has an interior space considerably larger than its outside dimensions, roughly 2 feet in diameter at the mouth and 4 feet
deep. The bag can hold up to 500 pounds,
not exceeding a volume of 64 cubic feet.
The bag weighs 15 pounds, regardless of its contents. Retrieving an item from the bag requires an action.
For more go to pg. 153 in D.M. Guide