I think you have a rare and valuable Skeet Model. Look on the barrels for the choke marking. If no numbered choke markings are visible, some Ithaca employee mistakenly marked the S on the forend when most skeet guns are marked with an S on the barrels. I hope Walt agrees with me. I just sold an identical rare and valuable 16 gauge Skeet Model that was marked S on the barrels. I'm sorry I sold it but I know where it is.