Sirs,
I've come across four DUIs that I can't identify in spite of considerable
effort. Please help.
1) Approximately 1-1/8 inch high, a red rectangular shield with
a hand grenade and a blasting machine upon it. Below is a scroll with
the motto, "Demonstramus".

2) This piece has no motto. It is about an inch square
rectangular shield. It is divided diagonally from upper left to
lower right. The upper area is dark blue with four stars arranged
like the constellation the 'Southern Cross'(like the stars on the
Americal Division patch). The lower area is red with a white
medieval tower with battlements at the top.

3) Approximately one inch high, a shield with a pointed bottom
and three points across the top. Extending 3/4 of the way down the
red shield and centered is a white wedge shape. A green lizard(a
chameleon?) is seen crawling across the shield towards the upper left
corner. No scroll or motto.

4) Barely an inch high and only 3/4 of an inch wide, the shield
is sharply pointed at the bottom, with three points at the top.
Divided diagonally from upper left to lower right, it is blue at the
top and red at the bottom. Superimposed over the shield is a 3/4
inch high evergreen tree. No scroll or motto.

Regretably, I do not have pictures of these pieces. My thanks in advance to anyone who can help. I have the great
honour to remain,
Your Most Humble Obedient Servant,
Kevin. J. Mansfield,
Adkins, Texas.

Originally Posted by silent driller

What's a DUI in this context?

Distinctive
Unit
Insignia

Also commonly, and incorrectly, referred to as Unit Crests. These are small metal and enamel pins worn by US Army units to identify a regiment, battalion or separate company/detachment (note my Avatar - the DUI of the 333rd FA Regiment). Normally these are derived from the unit's heraldic coat of arms and are worn on Berets (all colors) by NCOs and enlisted soldiers, Dress and the Class A and B uniforms. You also often see them on unit bulletin boards, signs and on earplug cases.

Let me get to work with me reference books and try to identify some of the DUIs - more to follow.

Update, was not able to ID any of the ones you describe, but will keep trying. Do you know what time period they are from and if they are truly US Army DUIs? They should have a manufacturer’s code (i.e. G23 or K33) and may say IRA Green INC or Vanguard and should say Made In USA if they are US DUIs.
Demonstratus (We Demonstrate) is the motto of the US 31st Engineer Battalion, but their insignia does not resemble what you describe at all. More to follow.

Ah. I figured it wasn't driving under the influence

Of course not!
Does cruising the internet count for the Driving part of DUI?

Not had much luck sorry kev the closest ive come to finding anything at all with Demonstramus as a motto is a patch for the USAF Orientation Group based at Gentile AFS OH but their patch looks nothing like what you have described will keep searching though
Christ this reply is now on its 3rd edit just found another link aswell 31st Engineer Battalion use that motto but I havent found a picture of their badge just a description of their coat of arms as follows
"SHIELD: Per chevron wavy gules and argent, in chief two mullets of the last, in base on a spade sable an edelweiss proper"
Hope that means something to you
Jay

p.s. can someone tell me how to add pictures to this thing as I have a picture of above mentioned crest and it wont let me paste it on
cheers

I found more DUIs on this page than any other. If they don't show a picture, look for the mottos.

http://www.vanguardmil.com/store/link1.php