Vietnam/Cold War Era US/ICS/Russian Navy Signal Flag "5" Marked "5"

Description

Here is a US/International Maritime Signal Flag. The flag is a yellow and blue divided triangle flag. For the US, ICS, and Russian Code of Signals it means "5"
I pin it around Vietnam/Late Cold War because the material it's made out of is indicative of materials that would've been used at the time.
It is marked "5"
Shipped with USPS First Class