155th (Mixed) Heavy Anti-Aircraft Regiment was an air defence unit of Britain's Royal Artillery formed during World War II. Around two-thirds of its personnel were women from the Auxiliary Territorial Service (ATS). After defending the West of Scotland and later London, the regiment was heavily engaged in Operation Diver against V-1 flying bombs, and later was deployed to Antwerp to carry out anti-Diver duties there in the closing stages of the war.

12th Anti-Aircraft Division was an air defence formation of the British Army during the early years of the Second World War. It defended Western Scotland and Northern Ireland, including the period of the Clydebank Blitz and Belfast Blitz, but only had a short career.