Distinctive Unit Insignia.  A Gold color metal and enamel device 1 13/32 inches (3.57 cm) in height consisting of the shield, crest and motto of the coat of arms.

The field is red for Artillery (blue would be for Infantry).  The gold billets are from the arms of Franche Comté, the canton from the badge of the parent organization.  The crest is the divisional shoulder sleeve insignia charged with the number of the regiment.

The distinctive unit insignia was originally approved for the 78th Field Artillery Regiment on 20 April 1928.  It was redesignated for the 78th Field Artillery Battalion (Armored) on 2 January 1941.  It was redesignated for the 78th Armored Field Artillery Battalion on 20 April 1954.  It was redesignated for the 78th Artillery Regiment on 17 November 1958.  The insignia was redesignated for the 78th Field Artillery Regiment effective 1 September 1971.

Shield:   Gules, billetté Or; on a canton of the last voided Sable, a sun in splendor of the second charged with the Arabic number “13” of the third (for the 13th Cavalry).

Crest:   On a wreath of the colors Or and Gules, a six point mullet Gules charged with the Arabic number “78” Or.    

Motto:   SEMEL ET SIMUL (At Once and Together). similarly (requires the teacher to instruct his pupils semel et omnes simul, "all together at one and the same time."

The DUI pin was optional as many units did not seem to have one. The oldest method is the screw-on pin which had one threaded stud and a large nut. Some old ones had a safety pin clasp. Most used the clutch-back pin which used two pointed studs with the modern spring loaded caps.

The designs of the DUI pin were intended to tell the story of the regiment's history and tradition that dated back to World War 1 or even as far back as the Civil War or Revolutionary

from: http://www.tioh.hqda.pentagon.mil/FA/78FieldArtilleryRegiment.htm

It appears than Irwin's unit
"Battery A 47th Armored Artillery Battalion"
1st under command of the 5th Armored Division and finally under the 2nd Armored Division.
The 78th Field Artillery Regiment was also under command of the 2nd Armored Division.
  Irwin may also have worked with the 78th to receive this Insignia.

Belgium remembers and honors the U.S. Armies of Liberation 1944 -1945
It lists
Second Armored Division, page 61 and Company "A" 47th Armored Infantry Battalion, page78
View: Information about the Liberation

There is a section on U.S. Army soldier names and 'Hutchings" is in there. (Maybe a mispelling)

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