Real-time measurements provided by seafloor pressure sensors are of great importance because lunar tides, storms, and tsunamis strongly impact pressures at the seafloor and the flow of fluids into and out of the oceanic crust. PRESTA301 is now installed at the Axial Base Site (MJ03A), and three more are installed within the Bottom Pressure and Tilt Sensors at the summit of Axial Seamount. PRESTA301 is a SBE 54 Tsunameter, and is connected to the MJ03A J-Box by a 10 m-long extension cable.