A bandolier or a bandoleer is a pocketed belt for holding ammunition. It is usually slung sash-style over the shoulder, with the ammunition pockets across the midriff and chest.

In its original form, it was common issue to soldiers from the 16th century to the 18th century, and contained either pre-packed chargers, small containers of wood, metal or cloth containing the measured amount of gunpowder for a single shot with muzzle-loading muskets or other guns; or early forms of cartridges also containing a ball. It might also carry grenades or other accessories for shooting. Any bag worn in the same style may also be described as a bandolier bag; similarly, pocketed belts holding ammunition worn around the waist may also be called bandoliers.

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