Zombie Jammer is a jammer block which, when enabled, a Zombie Jammer will prevent visitors of the world to be infected with the G-Virus, except with direct injection.
The Zombie Jammer glows green when activated. It has a big Z engraved on it, which stands for "Zombie". When activated, it makes a kind-of-whirring-like sound which can be silenced with the wrench. It also puts the "IMMUNE" tagline in green whenever people enter the world, to indicate that they are immune to the G-Virus as long as they are inside the world, or as long as the Zombie Jammer is activated. The Jammer can also be set to public, allowing anyone to turn it on and off. To activate one, punch it once, and to deactivate it, punch the jammer again.