Mounting components of photovoltaic (PV) modules and PV module assemblies are described, including PV module couplings and PV module mounting chassis. In an example, a PV module includes a PV module coupling having a toe portion extending from a PV module frame, and a PV module mounting chassis includes a toe slot to receive the toe. The toe and toe slot construction allows for the PV module frame to be assembled to the PV module mounting chassis without using tools, and thus, permits a PV module assembly to be quickly constructed during installation of a PV module system. Furthermore, the toe and toe slot construction accommodates thermal expansion and other environmental loads seen after installation, while providing a grounding connection for the PV module assembly.