These are basic functions, and most military backpacks in the world have their own additional functions, making them unique to their own countries.

Israeli military backpack
Inspired by the Israeli Defense Force (IDF) military, these military backpacks are a microcosm of durability, spaciousness, and practicality. They typically have many MOLLE functions, allowing for the addition of small bags or extra space when needed, and always have space for water bags to be consumed hands-free during travel. In order to truly experience the items used by real soldiers in the Israeli army, the tactical backpack of SOURCE was designed by former IDF soldiers and reflects the real bags used by the soldiers.
These backpacks do not have a one size fits all situation, there are smaller daily backpacks, such as this 10L military backpack, suitable for shorter hiking or tactical missions, and there are also larger backpacks, such as this oversized military backpack with a frame for added support.
British military backpack
British military backpacks are usually completely disguised or black. The British military is enthusiastic about including many MOLLES to allow for the connection of radio bags or other necessities, and they are also loyal supporters of the water bag system. Therefore, it is not surprising that the Source Virtus Soldier System is currently providing the British military with a complete set of equipment, including military backpacks.

Swiss military backpack
Although it is one of the most peaceful countries, Switzerland is famous for its simple, dark military backpacks. These bags are both fashionable and practical, almost always weather proof, making them perfect for travel, work, and even school.
German military backpack
These backpacks are sturdy and durable, with the most common having two long outer pockets for the convenience of soldiers. Unlike the Israeli and British armies, German soldiers usually carry a medium-sized military backpack with them, carrying everything necessary for combat.
US Military Backpack
The US military has very strict regulations on the colors of military backpacks that soldiers can use. These backpacks look no different from the backpacks of the British and Israeli armies, with many clips, extensive use of MOLLE, and water bags. But the rules stipulate that soldiers can only wear backpacks in the same camouflage color or pure black as their uniforms. Otherwise, they can only hold the bag in their hands instead of carrying it on their backs.
final decision
Although each country has its own unique type of military backpack, the goals of practicality, spaciousness, ruggedness, and weather resistance are common around the world. The tactical military backpack of SOURCE was designed with soldiers in mind and is very close to understanding the true working principle of military backpacks without the need for direct contact with them.
Overall, military backpacks are no different from civilian backpacks, but their durability and loading capacity are definitely stronger. Furthermore, due to their tactical definition, backpacks must have a higher appearance.