It came from Fabric Wholesale Direct. They have so much to choose from, and good prices!
Here's what those fabrics became. It's the H2O 2GO Sling waterbottle holder.
I had also ordered some webbing to use for the strap. I found an Etsy shop (AGraffSupplies) that carried some nice webbing and other supplies and was located actually only a couple of hours from here in Iowa. I placed my order, and believe it or not, got a shipping notification in just 11 MINUTES!! Can't beat that. Then of course, the postal service took it south to Des Moines and then back north the the Cities before they brought it here. (Where's the rolling eye emoji when you need it?)
Then I had to decide which to use. They didn't have a blue to match the canvas, so I had to decide between black and fuchsia, both of which would've worked nicely.
Fuchsia it was! Then to make it coordinate with the bag, I added some of the print canvas as an accent. Those Wonder Clips sure do come in handy, since the canvas shouldn't be ironed.
Ta Da! The finished strap!
And the finished water bottle holder, along with the biggest water bottle we have in the house.
It could, however, hold one considerably bigger... like a giant hydro flask.
Here's a closer look at the pockets. The zipper is installed such that the pocket only opens so far, so that whatever is in the depths of the pocket doesn't fall out. Brilliant!
So here you have it (and it looked so nice by my petunias that I couldn't resist).