Review on Soda Stream CO2 Cylinder Fill Station Adapter Kit - Easy Filling Solution for Soda Maker Tank (36 inch Hose) by Dana Mahendra

The TR21-4 adapter that comes with this particular vendor has a terrible internal seal and fails very quickly. This will cause a leak that will be visible through the filler neck. After carefully inspecting the assembly of my Sodastream I couldn't find any flaws so I started looking at the fittings on the adapter and hose, I immediately noticed that the gasket in the TR21-4 adapter was cracked and misaligned and it wasn't matched correctly. How that happens I couldn't tell, other than that it made me lose the entire contents of my CO2 tank as I didn't realize it until I was about to make my next soda bottle, so apparently it happened while I was sitting at our desk. Just bypass this brand, find an adapter with a good reliable rating of the TR21-4 adapter or buy that if you must and buy a separate adapter to have on hand.