Unangst

I am new to Benelli products. I am planning to purchase a Benelli Nova slug gun (model 20051). I see that Benelli offers a 3 round magazine extension for its H20 model, which is almost identical to the Nova slug gun, save for its nickel parts and its open rifle sights. So, I was wondering if anyone could tell me whether or not Benelli offers 3 round mag extensions for the model 20051 slug gun.