Subsea buoyancy foam for use on ROVs, AUVs, and any other underwater application. Using 3M glass beads, epoxy resin and other ingredients, it is moulded under high temperature and pressure to make a blank of certain size. This foam can be machined, glued, painted, and coated. Rovmaker can provide buoyancy material machining and surface treatment. Also available in fixed size or custom size material. There are buoyancy materials of different densities from the surface to the depth of 6000 meters. With its excellent hydraulic resistance and closed-hole structure, it has very low buoyancy loss and water absorption under long-term load. Good insulation performance, hydraulic crushing point at the pressure of 1-2 bar per second, the initial volume of the material has a 5% loss of the size of the pressure, the unit is bar.