Learn about the equivalent characterizations and proof techniques for strong collapsed Anosov flows in this second lecture of a four-part mini-course series on partially hyperbolic dynamical systems. Explore the mathematical foundations and theoretical frameworks that establish different ways to characterize these specialized flows, building upon the basic definitions and examples introduced in the first lecture. Delve into the technical aspects of proving equivalence between various formulations of collapsed Anosov flows, which are crucial for understanding their role in the classification of partially hyperbolic diffeomorphisms in three-dimensional manifolds. Master key concepts that bridge the gap between traditional Anosov flows and their collapsed variants, setting the stage for applications in accessibility and ergodicity that will be covered in subsequent lectures.