Carbonation Cap Diffusion Air Stone - Homebrew Carbonating Kits Including 5/16" Carbonation Cap, 2 Micron Diffusion Stone, 2 inch Beer Line, used for Soda, Water, Beer Brew

As others have mentioned, the tube fit is VERY tight, and you might have to work it back and forth to get it on. I have seen zero leaks so far, and it does really help my carbonation setup (simple tank and regulator) get a lot more CO2 into the water than just shaking the bottle alone. It's a bit harder to get the included male quick-release to pair up with the female one I've got for my setup, but it's not that much more difficult. I was quite careful to use gloves when touching the "stone" since they warn you about hand oil. It works pretty well and it's fairly low cost so it doesn't add much to my setup's total cost.

I carbonate my own spring water. I probably drink a liter of sparkling water each day and this stainless carbonation cap fits any standard plastic soda bottle such as a one liter or two liter soda bottle. It would also fit a smaller bottle but no point in that for me. I fill my bottles with flat spring water because it tastes better than what I get from my tap, not to mention all the impurities in my local water. After filling most of the bottle but leaving a little space in the top, I close it up and attach to my CO2 bottle regulated at 45 PSI. I do release the air after letting in some CO2, then seal completely, pressurize, and shake it up to absorb all the CO2. A few seconds later, I've got carbonated spring water. This is cheaper than paying a dollar per liter but it also means I won't throw away 350 liter plastic bottles in the trash each year. Amazon does sell a plastic version of this, don't waste your time. they are about the same price and this stainless cap is indestructible and looks cool. This one comes with a flexible tube and diffusion stone that releases the CO2 into the water with very tiny bubbles that absorb faster than just dumping in the gas. It's not totally necessary, but does seem to work well. The complete kit is very high quality and does exactly what it is designed to do.

Works great on our DIY home carbonated water system. With a hose, tank, and pressure regulator, takes about 30-60 seconds to make a 1 liter bottle of water if you shake it. Have had it for 3 weeks and have made about 3 liters per day. Several reviews report the tube is the wrong size, I disagree. Given the reviews I didn't even try to put it on out of the box, I heated up some water, placed the tube end in it and let it sit for a minute or two to soften it, then pushed it on by hand and with some pliers. The plastic is thick, wasn't worried about damaging anything. it's a great tight fit on both ends and my preference. You wont be able to pull it off though, I cut it with a utility knife because I wanted it shorter, put it in some hot water and reattached. Works for me

This really improved the consistency of my carbonated water. I wanted to give this five stars but just to many assembly and installation gotcha that instructions could have cleared up if they were included. First they are very generous with the hose. More than likely you will want to trim that so that the stone doesn’t bind up on the bottom of the bottle. This makes the cap really hard to get on and off. Second the hose is the right ID. Many reviews get that part wrong. It’s to thick. There is no reason to have it this thick. Even if you go to a full 80psi which is double working pressure (not sure stone is rated for that) and it failed it would be contained by the bottle. This tube is just too rigid for what you need. I will most likely replace it with hose rated for 40psi with more flexibility. As others mentioned for assembly dip the end in simmering hot water for 30 seconds. Grip the hose back where it is comfortable to hold. Press on with a rocking twisting motion.

Description states: 'Connect: Unique Machined the Carbonation Cap, can fit Grey Gas Ball Lock Disconnect and the Barb End Connect Plastic Tubing and Diffusion Stone' the the This is TOTALLY incorrect! the fitting is to large to fit the gas in fitting of a corny keg. I am returning this item immediately.

This thing is perfect. Much better than the plastic version you can find elsewhere. The air diffusion stone is the key to rapid carbonation. Trim the hose to the size you need (much more than 2” is provided) and you’re set. I’ve been pre-mixing cocktails, carbonating the whole mixture and it’s ready to rock. Again, the diffusion stone is worth the extra few dollars to properly quick carbonate COLD liquids.

The carbonation cap and filter are great, the tubing from China has a smell and that smell is imparted to whatever you put it in.

I bought this to help me make carbonated water. First the metal cap is solid! Very easy to install onto my 2 litter bottle. Second the co2 assembly is so much easier to snap onto this cap since it's metal & not plastic. Third, the diffusing stone creates small bubbles so I don't need to shake the bottle that much at all. Greatly recommend it!