The Breton shirt was officially created by the 27th March 1858 Act which introduced this blue and white striped knitted shirt in the uniform list of the French seaman.
It was said that this stripe allowed to locate more easily a man(or woman) fallen into the sea.

I have had one of these for the last 30 years. Can’t find them in Canada anywhere. Need a new one.

More great stuff at Armor-lux