This is a very solid shield weighing close to 1 1/2lbs and measuring 9" x 7 1/2". The actual bronze medallion is just under 3" wide...it is encased in glass but appears to be about 1/4" in thickness. The medallion has the TIGER emblem of the 13th Destroyer Squadron on one side and the US NAVY SEAL on the other.
I was advised that this is an old item dating around World War Two but I have no means of verification....am sure some Navy expert out there will be put me right on this !