325 Stainless Carbonation Cap with 5/16" Barb Ball Lock Type, Fit Most Soft Drink PET Bottles

This an all around excellent product.The construction quality is very high and it makes a standard 2 liter bottle look elegant.The internal gasket is very effective at creating a seal. I carbonate at 42 psi and I only need to gently tighten the cap with 2 fingers to get a gas-tight seal.The ball lock connection is very easy to connect/disconnect.I got this cap to replace the standard blue plastic cap and am very happy with the upgrade. My old cap was very difficult to tighten enough to seal. I would have to use a cloth to get enough grip, an adjustable wrench would have been better. Attaching the gas line to the old cap was even more difficult. I had to force it on with my body weight and my hand would be sore for a few days after. Not to mention the plastic looked cheap. After using this product for one day I threw out the old caps, can't recommend it enough.My only critique is that the check valve spring could be softer for rapid venting. I usually rapid vent and re-pressurize a few times to get higher quality bubbles and eliminate oxygen. On my old cap I could do this by pressing the check valve with my finger while the cap was screwed on. On this cap the spring is very strong so I have found it is easier to vent by unscrewing. Not a big deal since it is so easy to screw/unscrew this cap. I think it is just a strong spring is part of the high quality construction.I currently have two of these caps, one dedicated to seltzer, one for beer and cocktails. I plan to get several more so I can charge multiple drinks at the same time.

These things are great! Cold water absorbs co2 best, so in a best effort I prepare my drink in a 2 liter, and toss it in the freezer to get it as chilly as possible. Once I forgot about it and much of the liquid froze. With the bottle horizontal I was afraid the seal in this cap would be ruined after having iced up inside. This was not the case, it still performs as expected. If there is such a thing as a military-grade carbonation cap this would be it. Great design, very high quality. I have 2 and will be buying more.

My family uses these caps to make carbonated soda water. After 7 months of reliable daily use these caps have begun to leak and will not hold pressure. All rubber seals and o-ring are in good condition. The metal to metal contact of the internal poppet valve appear to be damaged, indicative of poor quality material or manufacturing. They can be disassembled for cleaning which I have done and reassembled but the caps are still leaking. I found no evidence of debri or hard water deposits. The poppet valve will no longer seal.

Bought this for carbonating water on the cheap. So far it's worked just fine. Occasionally it will leak a bit of air around the top, but twisting it back and forth a bit will make it stop. I haven't left it pressurized, so I don't know how it holds up to long-term pressure.

When we first set up our home carbonation system, I read so many different reviews for so many different carbonation cap products. We just use it to carbonate water, using standard water bottles. Ultimately, I settled on the blue plastic CarbaCap, because so many people complained about the stainless steel caps not fitting well. Well, we've had the system for several months now, and we've had constant frustration using the blue plastic cap. Mostly, it is very difficult to get a good seal, when tightening the cap down. Because it has no gasket between the top of the bottle and the inside of the cap, you're dependent on sheer muscle to crank it down. Then, it is super hard to remove. My wife can't even do it and has been constantly frustrated as bottle after bottle sprays water all over the place while she's charging it. Also, it was incredibly difficult to get the ball lock to fully latch onto the top of this cap.Finally, I decided to try this Stainless Carbonation Cap, figuring that for $11, I had very little to lose. Wow, what a difference! For starters, the cap has a nice gasket on the inner surface, which provides a fantastic seal to the bottle. It takes very little effort to tighten the cap or remove it, and there has been no hint of leaks. Next, the ball lock works very easily and snaps fully into place every time. My wife is thrilled - no more frustration when charging the bottles. Also, the threads on this cap seem to fit easier on the plastic water bottles too. There were so many times the blue plastic cap would thread crookedly and we'd have to keep backing off and re-trying to get a straight fit.So, if you're struggling, as I was, to decide whether to go the plastic route or the stainless route, I would strongly suggest you go for the stainless cap. Surprisingly, it was $5 less than the plastic cap, which had made me worried that is much be cheap junk. But I would say, now that I'm the owner of both products, that the CarbaCap is much cheaper in its design and quality than this stainless cap.Heck, even if I discover that I have to replace this every 6 months, if the inner gasket wears out, I'd happily go that route versus the constant frustration of trying to use the blue plastic cap.

Update: Have 3 of these - one came with a metal machining shard in a groove under the washer - removed it. After 1-2 years of twice-a-week use, the valve will not seat correctly on two of the three. My seltzer bottles still fill with CO2 but once supply valve-tubing detached, the valve does not hold the 2 bars of pressure in the bottle - you can hear the CO2 swooshing out over a few minutes. Tried rinsing with water and even applying a drop of vegetable oil down into valve - no help.Original Review: Very high quality heavy polished metal. Used it twice so far with CO2 at 40psi and 2-liter PET bottle and worked great to make seltzer. Food-grade CO2 tank, regulator (critical for safety), and https://smile.amazon.com/gp/product/B0064OI77Y/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1 all part of my setup. Gave this product and tubing a rinse and blew some CO2 thru it to remove any invisible manufacturing impurity residue (none were evident) before use. Came with replacement o-ring. Very good customer service on question about delivery time.

The description clearly says that it can be used to clean beer lines. However there are two issue:1- It is extremely hard to connect and disconnect (like when trying to connect the liquid line to the gas line incorrectly on a keg). So clearly not compatible with both type as they say.2- It leaks under the cap. Again should make no difference when using to carbonate but when trying to clean beer line it's a real pain. Tried to tight it but there is only a o-ring connecting an hex to a round connector so obviously will leak! Tried to add some Teflon tape which help but still leaked..