MRbrew Plastic Carbonation Cap, 4 PCS Ball Lock Keg Post 5/16'' Beer Line Nipple Barb Homebrew Kegging Soft Soda Drink PET Bottles Counter Pressure Bottle Filling Cap with Spare Sealing Gasket O-rings

I purchased a number of these to streamline carbonation of beverages in 1L bottles. These seal very well without any force at all on a 60# charge. They are sized so that two different brands of charging fittings go on and off equally well. Get a Bunch of these. Charge your drinks and refrigerate until use with these caps still on the bottle. Take them out and top them off at the time of use. Switch then to a standard cap if you want.

Works great. Plastic not too soft and wears well. Screw on tight. Based on how well these worked I upgraded to a Soda Stream. Would buy again

It works and it’s cheaper than the metal ones

These are great for making your own bubble water.

I've just started making my own seltzer so I have nothing with which to compare these caps. But, they are very solidly made (I was a bit leery of plastic, but they are impressive). They seal very well, and even came with some spare seals. Very impressive and hard to beat the price.I expect these will last a long, long time, but should any problems arise within the next six months or so, I'll hunt down this review and modify it.

As described. They’ve held up well to daily use.

These work just the way they should. No leaks. If I had to make one complaint it is that there is not enough knurling on them and that can make unscrewing them when they are sweaty a bit of a challenge.With four of these I can store bottles in the frige without depressurizing them. Very convenient.

I save the 1 quart soda bottles and refill with COLD (via frig) filtered water 3/4 full. Squeeze out the air, add one of these tops and tighten. Attach the ball cap fitting at 50 psi on the gauge and shake for 2 mins until you see very little bubbles coming out of the stem. I do 4 at a time. Then I unscrew the pressure cap, add a squirt of Stur or 1 tsp of Root Beer extract and vanilla and 2 Tbsp stevia sweetener... AND I use one of the other 4 bottles to top off each of the other 3! Put the old caps back on the bottles. Results in 3 full bottles. I do fresh squeezed lemon + lime too with 1/2 tsp of stevia. Easy way to make cheap soda's if you have the tank, gauge and hose around as beer/wine making equipment.