Pzr IV B - D turret armor 30mm , superstructure 30mm ( plus 30mm bolt on late D/E ). F - turret 50mm , super 50mm . G - J turret 50mm , super G - 50mm +30mm bolt on , H-J 80mm . Not much protection in any of them really . Goes back to the initial design as a infantry support vehicle . The Vorpanzer stuff might not be for everybody , the same with the Tauchpanzer , submersible details for those underwater traveling tanks for Operation Sea Lion . Maybe Rubicon can do a Panzer IV add on kit with all these weird bits and the late J exhausts , mesh side skirts , etc . I'm sure a few of us modellers are strange enough to want these weird , low produced tanks , wether there is a large enough market amongst the gamers to make it profitbale is another story . If not, I'm sure one of the after market companies could fill the void . They do make ARV add on resin / metal bits for the Cromwell , Sherman and Panzer III ., as well you can get AM turrets ( Sherman , Panther F , Whibelwind ) and dozer blades . I'm sure its just a matter of time till more AM parts are released