Below are some links that I use. The first section is useful references. The second section includes people that I trade with and recommend as trading partners.
Insignia References
American Society of Military Insignia Collectors (ASMIC). The oldest and largest organization for military insignia collectors in the world. I highly recommend that any serious collector joins ASMIC.
The Institute of Heraldry. The official US Army web page for insignia.
Personal Web Pages - Recommended Trading
Partners
Dave Dawley - ASMIC member. Trades US Army SSI and DI. Focused on Corps of Engineers.
Jim Placke's NBC Links - The best source of Nuclear, Biological, and Chemical warfare that I've found. Jim collects NBC related insignia and has a very good section on Chemical Corps patches and DI. He is an ASMIC member.
Giannis Tsiris - Collects and trades military parachute wings. Very complete selection of Greek airborne wings and patches plus other foreign airborne wings for trade.
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