what is a flare pen
No, the pen flares are not DDs, they are a pyrotechnic signaling device. However some states may have restrictions due to fire risks. There are numerous companies that make pen flares for civilians and mil, and if you can place an order for thousands (or tens of thousands) of them, you can get the same ones the mil are using. Here is the main one that sells to civis: http://www.truflareusa.com/product_catalog.htm