MuCell® Microcellular Injection Molding (MIM) is a key green technology that reduces energy consumption and material usage while facilitating recycling. Despite its benefits, surface defects and inconsistent foaming remain challenges. Gas Counter Pressure (GCP) has been introduced to improve foam morphology, but conventional methods often suffer from pressure instability. This study investigates the impact of a stabilization device in GCP-assisted molding. Results show that stabilized GCP increases cell density by approximately 41% compared to conventional GCP, and reduces the standard deviation of cell diameter from 2.54 µm to 1.77 µm. These improvements significantly enhance cell uniformity, underscoring the broader potential of MuCell® technology in plastic manufacturing.