Home Use Soda Refill Bottle CO2 Cylinder Cartridges, Adapter Refills Connector Kit CGA320 to TR21-4, Thread Set Replacement Accessories for Soda Machine Tank, Gold

Not much to say about this, it feels strong and solid, and fills my carbonation machine bottles simply and easily. The only thing I would like to see improved in the design is an internal lip or catch to keep the ring gasket seated in place. When a bottle is not attached it can fall out, but this doesn't affect the usability of the device, just the ease of use. Overall great product that will save an enormous amount of money compared to exchanging bottles.

Works well, but the small O rings break easily. The package needs to have more O rings included. Most important to fill the canisters SLOWLY.

Great price and extremely easy to use... just have to open the valve slowly whit the tank up side down to get the liquid out to refill the bottles, you do not want the gas to fill the bottle, so far filled 2 bottles without a hiccup, bottle actually seem to get filled more than when you purchase them new, I felt them heavier than when replaced by Sodastream. A refill of a 5Lbs CO2 tube is $15 ($25 for a 20Lb), you can fill at least 5 of the small bottles with the 5Lbs, it pays itself off very fast if you use your soda machine as I do.

EDIT:I left the positive review below a few months ago, but now have to revise downward for one simple reason. The metal used on the relief valve thumbscrew is utter garbage. After only a few months of use, the head completely sheared off while hand tightening this valve, leaving the unit useless. Looking at the broken off edges, it appears to be cast form extremely low grade, weak, pot metal. A pity, too, because the brass connector itself appears quire well made.Dropping this to one star and recommending you look somewhere else, as this unit just won't hold up.ORIGINAL REVIEW:I picked up one of these to fill classic Soda Stream CO2 tubes from a 10lb tube I use for a kegerator setup, and so far it has worked out quite well. It's machined from solid brass and is quite effective if you know what you are doing. I'd give this five stars, but the o ring on the relief valve was installed incorrectly, so it leaked out of the box. Luckily, it included multiple replacement O rings, so it was an easy fix.Some use tips:1. Your Soda Stream tube MUST be at freezing temperatures in order to fill properly. This is because the pressure CO2 is liquid and will gassify as it hits the warm tube, preventing a full fill. I put mine on ice about an hour before filling for best results.2. Point your source cylinder DOWNWARD while filling, which will allow the CO2 to flow into the Soda Stream tube.3. Open the valve on your source canister slowly, until you hear the gas flowing. The Soda Stream tube has a lockout on the pin that will prevent the flow if you open the valve too quickly.4. After you've filled your Soda Stream tube, close the valve on your source cylinder, and turn the relief valve on the coupler to vent excess gas. This will make it a lot easier to remove the coupler.5. Since this is an unregulated coupler, this will fill until the pressure on each side is equalized. Therefore, your best fills will come when your source tube is full. If you are filling from an emptier cylinder, your Soda Stream tube will not fill fully.

Filled up my CO2 on the first go.Helpful tip-- DO NOT USE the RELEASE VALVE.The very first time I used it, the o-ring blew.You will know if it blows because the next time you go to fill a bottle there will be slight leak because the release valve won't have a closed seal.They only give you four extras, but if it happened on the first time I'm just not going to use it. There's not much pressure in the fitting space between the soda cylinder and the tank.Otherwise it works as expected.I had one with a hose and it was just ridiculous with the wasting of the CO2. You don't need a gauge. I would have been happy to stick with the hose one however it imparted a funny taste into my CO2 so this works great.I filled super slowly on the first go but probably too slowly because I was sitting there for like 8 minutes and it still was going. I went to video they had on the little instruction booklet just to confirm.I think it's weird how and none of the instructions say to close down the release valve before you start filling in case someone didn't know- for someone who's never done this it is helpful to know that the release valve should be closed before you fill.Anyways you don't even need it Don't use it seriously.Also like another reviewer said I stacked the clear plastic o-rings together on the SodaStream side because it just fit better and it works.

The round o-ring on the big tank side works well and forms a good seal. The flat washers, for the drink tank side, is too thin to form a seal so I wound up just putting both flat washers in there to get it to work and will look for a thicker one at some point. The bleed screw is horribly designed and should not be used. I blew the super-tiny o-ring the few times I tried using the bleed screw so I stopped using it. I found it was just easier to unscrew the tank and released the pressure that way. On the drink tank side, there is a valve depression point that can be adjusted or removed. Adjusting it is very easy, and it may need additional adjustments if it moves in or out over time. Given all that, I'm able to fill the tanks full each time and check the weights with a scale. All my drink tanks are the anti-fill type but when going slow they all fill properly. I don't empty the drink tank before filling, if done properly there's just no need. Please secure any big tanks, wear gloves, eye protection etc and use in well ventilated space.