I was an 82C20, Artillery Survey, of all things. We surveyed the battery areas before they moved the guns in (a composite battery 8 inch/175 guns). I actually served in my MOS exactly 1 day in 'Nam, mostly I drove a truck or fixed trucks or ran a radio in the ROK division HQ we were attached to. I don't remember that card, though, the vests we had were really old, handed down many times. The card sort of seems like the one on parchutes "If this chute ever fails to open, take it and this card to ..." ;-) You know, Vietnam is getting to be a long time ago, for the young guys here it is farther back in history than WWII was for us.