The Affordable Robust Compact (ARC) reactor is a conceptual design of a nuclear fusion reactor developed by MIT Plasma Science and Fusion Center; its main objective is to demonstrate the feasibility and the advantages of compact high magnetic fields - produced by REBCO high temperature superconducting tapes in demountable field coils - and of inboard radio frequency lower hybrid current drive launchers, ensuring a steady state condition for plasma and the consequent power generation. ARC includes a fully liquid blanket consisting of FLiBe: a molten salt made by a 2:1 LiF-BeF2 mixture, therefore serving, simultaneously, as tritium breeder, heat-transfer fluid and neutron shielding material.