Ferroday Stainless Steel Carbonation Cap Forced Carbonation PET Bottle Filling 5/16 Barb CO2 Coupling to Carbonate Soda Beer Stainless Steel PET Bottle Carbonation Cap + O-ring + Gasket

When we got the carbonation lid for our corny keg, we were trying to figure out a way to provide carbonated water during the 2 days it would take to charge a fresh keg, and found these (same brand). The idea of being able to take a bog standard 2 liter bottle and charge carbonated water in it was, TBH, mind blowing, so I decided to give it a try, in the hopes it would give us a backstop while the keg recharged. The cap itself is cut on the sides allowing you to use a keg spanner to tighten it up, a really useful feature for us with physical disabilities that make grip an issue. It works so well! One thing that we did though was to get some liquid tubing, and a pair of micro porous stones (Ferroday again). We hooked the tube and stone up, in the hopes we could get the micro porous stone speed, and easier to store standing up while it charged. It works well in both cases. So for 3, 4 hours of charging, at 35psi, we get a 2 liter bottle of carbonated water. Any short of a time doesn't seem to work, but I don't know if this is a limitation of the carbonation cap or operator error, as I've seen YouTube videos that claim less than an hour to charge a bottle. I'd recommend this, both for charging a 2 liter bottle before going out, or as we're using it, to make sure we have standby fluids. If you're using this alone, rather than with the upgrades I mentioned, remember to lay the bottle on its side in the fridge for the tube to be inside the liquid.

I have had an original carbacap that I have been using for quite literally for 15ish years. They were made of nylon and work really really well, annoyingly I dropped the water bottle after it was carbonated with the cap still in place and the pressure bump from the drop (I carbonate to about 70#) was enough to make it start leaking co2. They havent been available for years and I saw the many good reviews for this and gave it a try, honestly I was pretty skeptical. I have tried a number of different caps over the years and have never found anything that works as well and that old one. They were bought out a number of years ago and the newer versions arent as good being made from a plastic resin, the original company name was liquid bread, if you ever spot one somewhere snap it up. I was delighted to find this has worked really well so far, Ive only carbonated a few times with it and Ill edit this if that changes but Im very happy with it so far. The only criticism I have is the outside shape, the round outside makes it slippery and not easy to get on and off, but that wont stop me from using it. Ill just be occasionally annoyed when I do, but Im easily annoyed anyway...lol

My local home brew store could not provide me with one of these that worked. It was plastic trash that would not work with the ball lock they set me up with. I thought maybe it was a defect and returned to see if I could get a refund or exchange, and they couldn’t get it to work either, and a new one also would not work. This one is well-built, looks good, fits on standard bottles, has no leakage, and costs less than the name brand, plastic junk.

I use these for two purposes (both with a 10lb CO2 tank). 1) I buy soda in 2L bottles because on sale it is usually a lot cheaper per oz. A 2L bottle fills up four 500 ml bottles perfectly and I just squeeze out the air and tighten the cap and fill it up with 30psi of CO2. Far less plastic being used and less money being spent over the years. 2) Making my own seltzer water by attaching the inner barb in this cap to the tube connected to this stone: https://smile.amazon.com/gp/product/B091C5Y6L9 and squeezing out the air, tightening the cap and attaching the CO2 to this cap and shaking away. There is a plastic version of this that I tried because this is a bit heavy, making the bottle top heavy, but that cap only works on specific bottle, while this works on all bottles because they use easily replaceable washers. The plastic one costs twice as much as this metal one. The plastic one also does not like being fully attached to the CO2 hose as it wears away at the plastic over time. This metal one should not have that issue. One also would not have to worry about the plastic version rusting or leaving metal shavings behind which I have seen in other reviews but I have not yet experienced myself. Nor have I experiences any issues with sharp edges as I have seen in 1 of these reviews. Note that this appear to be 100% identical to the ones sold by KegCo, which I bought first, but these come with extra washers, which is a very nice touch.