Does anyone know what this pouch might be? It has an Army and Navy Stamp and the name of a Royal Artillery serviceman written on it. It looks like part of a Sam Browne belt or a saddle. It has a number of attachments but its not immediately obvious how it might attach to something or what it may hold.

When the lid is off you can see two grooves at either side of the opening so that whatever the pouch holds can be gripped and removed. An ammo clip?

Thanks in advance..

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