 This paper investigates the use of phase change material, PCM, integrated thermal control devices, TCDs, on small satellites. The authors design six different pin fin geometries and test them in a vacuum chamber to determine which one provides the best thermal performance. They found that the cross-shaped, I-shaped, and V-shaped pin fins provide the most significant improvement in thermal performance compared to the circular fin geometry. Additionally, the V-shaped fins can increase the PCM melt fraction by 32.3%. This article was authored by Abdul Rahman M. Alshar, A. M. Solomon, M. Kasab, and others.