WW2 era, A.R.P., Air Raid Protection, Members Pin

WW2 era, A.R.P., Air Raid Protection, members pin. Gray coated white metal, 38.47mm high by 25.88mm wide, with pin back fastener. There is a small egg shaped dent near the letter R, left side, about half way down, otherwise excellent. Quite heavy, much heavier than often found.
Control #WS13118