Assembly crews at the ITER facility successfully lowered the sixth tokamak sector module into the reactor pit on 28 July. Primary confinement boundary for plasma The vacuum vessel serves as the primary confinement boundary for the fusion plasma inside the reactor. They place a central 440-tonne double-walled vacuum vessel sector between two toroidal field coils, which weigh approximately 310 tonnes each, and attach thermal shield panels. The sixth module centers around vacuum vessel sector number one, which is the fourth and final sector manufactured by the Republic of Korea. Result of international collaboration Representatives from Korea and the ITER Organization gathered on 22 July for ITER Korean Fusion Day to celebrate the completion of Korea’s vacuum vessel manufacturing program.