WW2 Fire Watcher civilian volunteer gentleman's war worker lapel badge

A scarce original wartime period volunteer 'Fire Watcher' gilt lapel home front badge; flaming grenade inlaid with unusual dark red enamel and bearing variant letters 'FW' within outer horseshoe title in dark blue. Good condition, complete with original buttonhole lapel fitting, no loss of enamel, but with dark underglaze marks to red. Height 22mm.