Came across this site with representations of Distictive Unit Insignia of Gas/Chemical units. Some are using the shield of the units CoA but others are using a badge variant.
I rather like the 304th’s. It uses an octopus. That is an animal I never really thought of in a heraldic sense. But, it works and looks great. 
I agree. That’s the one that really caught my attention.
I don’t think i have seen a Octopuss used in Heraldry before but it surly makes a distinctive charge.
http://www.tioh.hqda.pentagon.mil/Graphics/155ChemicalBnCOA.jpg
The CoA of the 155th Chemical Battalion was approved on 11 December 2006.
Blazon:
Shield: Per chevron abased Azure and Gules, a hexagon in chief surmounted by a chevronel Or, counterchanged of the field, in base a hydra of the third.
Crest: That for the regiments and separate battalions of the Ohio Army National Guard: From a wreath Or and Azure, a sheaf of seventeen arrows Argent, bound by a sprig of buckeye (aesculus glabra) fructed Proper (two leaves with bursting burr).
Motto: THE FOG OF WAR.
Symbolism:
Shield: Yellow and blue are the traditional colors for the Chemical Corps. The hexagon shape reflects the benzene ring. The chevron division symbolizes the swallowtail design on the Ohio State Flag. The hydra (a multi-headed dragon) represents the dragon theme used in Chemical Corps designs and the multiple missions of the Chemical Companies within the 155th Chemical Battalion.
The Crest is that of the Ohio Army National Guard.
Marcus K wrote:
Came across this site with representations of Distictive Unit Insignia of Gas/Chemical units. Some are using the shield of the units CoA but others are using a badge variant.
What’s interesting, inter alia, is the frequent use of the term "transparent" in the blazons, but this is surely a detail of manufacture rather than part of the blazon proper.
Daniel C. Boyer wrote:
What’s interesting, inter alia, is the frequent use of the term "transparent" in the blazons, but this is surely a detail of manufacture rather than part of the blazon proper.
It would seem so, or perhaps just an insignia collector’s way of describing the differences between different production runs of the same badge. The Institute of Heraldry’s site blazons these, for example as:
2d Chem Bn - Or, a dragon segreant with wings inverted Gules armed and langued of the like clutching in its front claws a lightning bolt Azure, its dexter hind paw resting upon an automobile wheel Proper.
4th Chem Bn - Or, issuant from an Aladdin’s Lamp in base clouds forming a genie with clenched dexter hand Azure, in sinister chief a mullet Gules.
And so on—no mention of "transparent."
