You'll need to make sure that the other players have the .mat file on their machine, otherwise they'll see your saber as a gray block with yellow stripes in it.
You'd either need to specify a download site for the .mat file, or incorparate it into a patch, meaning all players would have to have it active, guaranteeing that they will see it. (Use a program such as ConMan to make patches, incase you didn't know
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