I had returned from my last trip, dumped all of my backpack gear in the middle of the floor of the gear room, and cleaned things up. Just now I was getting ready for the next trip, and I was laying everything out according to my gear checklist. Unfortunately, my gravity feed water treatment kit was missing. That consists of some Platypus hoses, a small filter, and a couple of 2-quart Platypus containers. Those are all within one plastic bag. I don't know whether I lost the kit on the end of my last trip, or whether it ended up in my car or my garage. I've gone over the gear room from top to bottom. However, due to the time schedule of my next departure, I didn't have much time to replace it in an economical fashion, so I simply drove to the nearest REI store with the intention of buying a couple of replacement hoses and a filter. To my dismay, REI doesn't stock all of that stuff anymore. They had all sorts of $70 or $100 or higher water filter kits that were heavy and overkill. Rats!
To my disgust, I purchased the Platypus Gravityworks, which is another gravity system. When I got it home, I discovered that they don't even put generic hose connectors on both bags. One bag has a proprietary connector. Those scoundrels!
So, I have something that will work for the next trip.