WW1 On War Service 1915 munition workers badge

A scarce original First World War period gilt and enamel war workers badge, within a blue enamel rimmed seeded gilt circlet surmounted by Union spray of rose, shamrock and thistle; the central patriotic 'S' ribbon style scroll inlaid with red, white and blue enamel and inscribed 'On War Service 1915'; the reverse with maker's details 'Thomas Fattorini Bolton' and impressed 'Reg.638232' a registered, design and patent date of 1914. Exceptionally good condition, complete with original buttonhole fitting, no damage to the enamel, gilt finish remains bright. Diameter 27mm.