CFS's ARC reactor design will use a FLiBe molten salt blanket to shield everything except the vacuum chamber itself, which is a steel doughnut with 2cm thick walls. They plan to build a proof of concept reactor by 2025 that will have net energy gain (Q > 10), and then a full demo power plant by 2030. CFS believes they can move faster than ITER because the newer stronger magnets that they're using make smaller reactors viable. Smaller scale means cheaper to build, which means a nimbler private company can build it rather than a bureaucratic international project.