FLAG curiosity??

This flag has some interesting features?https://www.milsurps.com/images/impo...tocks038-1.jpghttps://www.milsurps.com/images/impo...tocks039-1.jpghttps://www.milsurps.com/images/impo...tocks040-1.jpg
The four corners have a @4x4 patch sewn in. What is that done for? And the braided rope that is sewn into the flag and was cut? Where would this flag have been flown. It was said to be a U boat flag but that Ensign was totally different. I am only interested for historical purpose the flag is on its way back to NJ.

Surely those corners were sewn like that to strengthen the flag up for a harsh life. We still have flags with strengthened corners flying at work today and we only have to put up with moderate winds on Salisbury Plain!

That was my thought too, thanks Peter.

Correct my comments as fromn about an hour ago. Today we have absolutely howling xxxxxxg winds storming across Salisbury Plain! It's bending the tank aerials right back, especially those ones with flags attached!