The battle bag, or Mann bag, is a lightweight load carrying system designed to allow the combat infantryman to carry enough ammunition

Ammunition

Ammunition is a generic term derived from the French language la munition which embraced all material used for war , but which in time came to refer specifically to gunpowder and artillery. The collective term for all types of ammunition is munitions...

 and ancillaries such as medical supplies, spare batteries

Battery (electricity)

An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...

, and radio equipment

Radio equipment

Radio equipment, as defined in Federal Information Management Regulations, is any equipment or interconnected system or subsystem of equipment that is used to communicate over a distance by modulating and radiating electromagnetic waves in space without artificial guide...

. There are a multitude of different suppliers for these, with the British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

 having designed its own version for issue under the PECOC programme. The key compartments, or pouch

Pouch

Pouch may refer to:* A small bag such as a pocket, teabag, money pouch, sporran, etc* Cadaver pouch, body bag * Diplomatic pouch* Electric heating pouch, medical apparatus, electric heating device for curative treatment...

es, on the battle bag consist of the main compartment, 3 to 4 ammo pouches, an FFD (trauma dressing

Dressing (medical)

A dressing is an adjunct used by a person for application to a wound to promote healing and/or prevent further harm. A dressing is designed to be in direct contact with the wound, which makes it different from a bandage, which is primarily used to hold a dressing in place...

) pouch, and a radio pouch, which is usually mounted within the main compartment. Some designs of battle bags have MOLLE

MOLLE (military)

MOLLE |female name]]) is an acronym for MOdular Lightweight Load-carrying Equipment. It is used to define the current generation of load-bearing equipment and rucksacks utilized by the United States armed forces, especially the United States Army, and its use is also growing in the British Army in...

 strips on them, to allow the user to accessorise the bag to their operational requirements. Others, such as the BlackHawk bag, have an internal map case.

The battle bag was originally designed for use as a "grab bag", to allow drivers and vehicle-borne troops to grab essential supplies in a dismount for such functions as an ambush

Ambush

An ambush is a long-established military tactic, in which the aggressors take advantage of concealment and the element of surprise to attack an unsuspecting enemy from concealed positions, such as among dense underbrush or behind hilltops...

 or the assault phase of a mechanised attack. From there, it has spread in popularity with troops due to its ability to be worn comfortably over body armour, as well as the fact that it can be rapidly removed from the wearer in a medical emergency

Medical emergency

A medical emergency is an injury or illness that is acute and poses an immediate risk to a person's life or long term health. These emergencies may require assistance from another person, who should ideally be suitably qualified to do so, although some of these emergencies can be dealt with by the...

, or to allow the wearer to crawl through "mouseholes" (small jagged holes blown through compound walls with explosive charges).