The hulls of U.S. Navy submarines are made with armor plate rolled on Coatesville’s 206” Rolling Mill. Shown is the USS Ohio (SSBN-726), the first in the Ohio-class of nuclear-powered ballistic missile submarines. Launched in the 1970s, these submarines were designed for stealth and the precise delivery of nuclear warheads. The Ohio remains active in the U.S. Navy today as a guided missile submarine (SSGN).