I just picked up these 2 Vietnam era helmets, and I noticed a few differences between them. First the color seems to be slightly different between their covers. This may be just due to age and wear, however the contract numbers "8027" seem to date them both to 1964-65. I was wondering if there was a difference in the colors or patterns based on the manufacturer or is this just due to wear from usage and washing?

Also, one of the chinstrap buckles has an anchor on it and the other did not, I was wondering if the anchor on the chin strap represented something?

Thanks

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