A few asked how do I cap my windsocks specially when I guide. I simply add a pushnut under the top rubber washer. Although alot like it uncapped because its easier to remove the sock to wash.
I like to cap it because they sometimes fall off if you pick up by pulling the bag.
Here is where I get my caps from. They are very cheap ($5 for 100) and fit perfectly.
https://www.clipsandfasteners.com/1-4-Pushnut-Bolt-Retainer-1-2-O-D-Zinc-p/a10086.htm