attaching brass shell casings

We're attaching three spent shell casings to a mat backing, and I'm thinking about how to do it. The customer's fine with hot glue, and we only use the non-corrosive electrician's kind, but I'm thinking a mechanical hold would be longer lasting and less interactive. (Too, the hot glue has a set

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, Item Number: , 1511-36749, Item ID: , 2276, Category: , Casings

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