The Panzer IV chassis proved ideal for experimenting with new weapons derived from Rift-tech. The most prominent of these is the Panzer IV X that mounts a gravity pulse cannon (the Schwerefeld Projektor).
Still only produced in limited numbers, its success in battle means it will undoubtedly be seen regularly in the future.
Full rules can be found on page 137 of the Konflikt '47 rules book.
Models supplied unassembled and unpainted