My Verona 12ga came with 4 choke tubes and they are only marked with some cutouts on the edge of them, no writing. One has 1 mark and one 2, one 3 and one 4. Is there any way to tell which size is which?

Also, if I just wanted to go out and buy a choke tube, so I knew FOR SURE what it is I have do I have to get a Verona tube, or will any tube made for a 12ga gun work?

Thanks;