Ripstop by the Roll has been my #1 place for top-notch fabrics and hardware for many years. I've made hammocks with zippered mesh covers, rainflies, added pockets to backpacks, bikepacking bags, etc, and it all starts at here.
The HHH Waterproof Coil Zipper was a fist-time purchase, and it did not disappoint! I built a bikepacking top tube bag that spans from the headset to the seat tube, and I wanted a stout zipper that could be opened and closed with one hand. I put two pulls opposite each other so the bag is closed when the pulls are at opposite ends. This allows me to access one side it the other without opening the whole thing.
I highly recommend this zipper I was able to open and close the bag with one-hand while still riding everytime on a recent bikepacking adventure.
If I had to remake this bag again, I'd do it exactly the same.