In industrial settings, working with mixtures of different phases and materials often complicates direct measurements and experiments, highlighting the need for complementary modeling techniques. The Discrete Element Method (DEM) is commonly used to simulate granular material flows, typically with coarse-grained spherical particles [1]. However, certain applications, like recycled polymers and batteries, require alternative non-convex particle shapes in DEM simulations. Tetrapods have emerged as a promising candidate for representing such materials and the uncertainties associated with their behavior. This study explores the effect of tetrapod properties on both the simulation results and the uncertainty inherent to a DEM model. We show that tetrapods are well-suited for modeling interlocking materials, with their shape and size playing a significant role in interlocking behavior. Interestingly, we find that the uncertainty of our simulations is positively related to both the size of the tetrapods and the interlocking parameter ξ/D, which measures the tetrapods’ non-convexity. Finally, we provide practical guidelines for selecting the most appropriate tetrapod parameters to accurately model materials, based on mean and variance of an experimental data set. [2]