What defines an integral mortar?

An integral mortar is specifically designed as a pre-loaded device intended for single use in pyrotechnic displays. This definition emphasizes that an integral mortar comes ready with a pyrotechnic item already placed inside, which is not intended to be reloaded or reused after its initial activation. This characteristic is crucial for ensuring safety and reliability during fireworks displays, as each integral mortar is uniquely suited for a specific effect or design, and is constructed to handle the pressures and circumstances specific to that single use.

The other choices describe different aspects or types of equipment related to fireworks. Holding multiple pyrotechnic devices pertains to broader mortar structures or racks rather than individual integral mortars. A container for the storage of fireworks does not relate directly to the operating nature of an integral mortar, and a control device for pyrotechnic effects involves the operational mechanism rather than the physical properties of a mortar itself. Each of these choices, while relevant to the field of pyrotechnics, does not accurately capture the essence of what constitutes an integral mortar.