A self-expanding bag is a type of storage solution designed to increase its capacity when needed. Typically made from flexible materials, it can expand in size to accommodate more items, making it ideal for various uses, such as travel or shopping. When not in use, the bag can be compressed to a smaller size for easy storage. These bags often feature adjustable straps or zippers that allow users to control the expansion. Some models may include additional compartments for organization. Self-expanding bags are popular among outdoor enthusiasts and urban dwellers who require versatile and space-saving options for carrying belongings.