This medal "The Defence Medal" was issued between 3rd september 1939 and 2nd september 1945.

The 1939-45 Defence Medal was a campaign medal of the British Commonwealth, awarded for service in World War II. It was instituted to recognise both military and some types of civilian service.

This type of service in the UK includes, but is not confined to, those civilian personnel who worked as members of:

Home Guard
Royal Observer Corps
Fire Brigades, including the National Fire Service (NFS)
Civil Defence Messenger Service
Police
Coast Guard
The qualifying time required depending on the area served is:

UK - 1080 days
Overseas non-operational - 360 days
Overseas non-operational in an area deemed to be closely threatened or subject to air attack -180 days

A circular, silver (.800 fine) medal, 36mm in diameter. The British issue medals were made of cupro-nickel.
The obverse shows the bareheaded effigy of King George VI, facing left, and the legend: GEORGIVS VI D:G:BR:OMN:REX F:D:IND:IMP:
On the reverse, the Royal Crown rests on the stump of an oak tree, flanked by a lion and a lioness. At the top left is the date 1939, and at the top right, the date 1945. The base of the medal has the words 'THE DEFENCE/MEDAL' in two lines.
The ribbon is flame coloured in the centre flanked by stripes of green to symbolise enemy attacks on Britain's green and pleasant land, with narrow black stripes to represent the black-out