Grolsch Flip-top Bottle (750 ml)
Product Review (submitted on January 20, 2014):
When I started making water kefir soda, I ordered two of these bottles. Then I bought two "similar" bottles at a local store. The Grolsch bottles make bubbly water kefir, but the store bought ones don't! My only regret is that I didn't order six of these right from the start! The top stays so tight that it is tough to open, but this is precisely why it works so well. To make it easier to flip, I wrap a towel or a piece of rubbery shelf liner over the top to help me get a good grip.