IWC Mark XI British Air Force Issued Ref 6B/346Launched in 1948 as a collaboration between IWC and JLC, the Mark XI was crafted to meet British Ministry of Defense (MoD) specifications, producing timeless classics with similar styles. While JLC discontinued production in 1953, IWC continued until the Mark XI's decommissioning in the early 1980s. Adhering to MoD standards, the Mark XI featured a broad arrow designation on the dial, movement, and case, signifying government property. Models after