WW1 On War Service 1915 munition workers badge J.A.Wylie.

A good original Great War period official 'On War Service 1915 munitions workers badge', the voided centre bearing the 'Board of Ordnance' shield; the reverse with maker's details stamped in relief 'J.A.Wylie & Co London' and impressed with official issue number 'Z30337'. Very good condition, retaining original buttonhole fitting. Height 44mm.