The Power Block Kit is required to upgrade FX Impact MKI (x) models to MKII. While the Power Plenum expands the Impact’s power potential, the rear block is what helps deliver that power efficiently—much like a ported and polished intake manifold on a high-performance engine. This upgraded valve house improves airflow, efficiency, and overall power capability. The Power Block performs especially well in higher-power setups, particularly for shooters using heavy slugs, where increased speed and energy are the goal.
