The MOLLE 4000 rucksack fills the gap between the large and medium rucksacks for paratroopers.
The MOLLE II Large Rucksack has an approximate internal volume of 2900 cubic inches in the top compartment and 830 cubic inches in the lower compartment, and is capable of carrying a 120-pound load.
The MOLLE II medium rucksack has a volume of approximately 3,000 cubic inches.